Device for measuring calorie expenditure and device for measuring body temperature

ABSTRACT

In order to obtain calorie expenditure with good accuracy, the device is provided with a basal metabolic state specifying element (142) which specifies the subject&#39;s basal metabolic state from his body temperature; a correlation storing element (151) which stores respective regression formulas showing the correlation between the pulse rate and the calorie expenditure when the subject is at rest or active; a correlation correcting element (152) which correcting the stored regression formulas using the basal metabolic state; a body motion determining element (104) which determines whether or not the subject is at rest; and a regression formula selecting element (153) which selects the regression formula which should be used in accordance with the results of this determination. The subject&#39;s pulse rate is applied in the selected regression formula, and the calorie expenditure corresponding to this pulse rate is calculated by calorie expenditure calculator (162).

TECHNICAL FIELD

The present invention relates to a calorie expenditure measuring devicewhich can accurately measure the calorie expenditure by a subjectregardless of whether the subject is resting or active, without beingeffected by such factors as the temperature of the surroundingenvironment, daily or annual fluctuations in the subject's physicalstate, this device accordingly being useful in maintaining health. Thepresent invention is further related to a body temperature measuringdevice suitably employed in the aforementioned calorie expendituremeasuring device which can continuously measure a body temperature whichis as close as possible to the subject's deep body temperature, and istherefore also useful in maintaining health.

BACKGROUND ART

In this time of abundant food, calorie expenditure during exercise ordaily activities has been recognized as one important index formaintaining health. Accordingly, the determination of calories expendedis very significant. The standard total number of calories expendeddaily may vary widely, from a minimum of 1,000 kcal for a 1-year oldchild to a maximum of 3,800 Kcal for a 17-year teenager.

When measuring calorie expenditure, accuracy of within about 5% of theminimum value is considered necessary. Accordingly, the measurementerror must be within 50 kcal.

Calorie expenditure measuring devices, such as th at disclosed inJapanese Patent Application Hei 8-52119 for example, has been proposedas devices for measuring the body's calorie expenditure. Such calorieexpenditure measuring devices record the subject's sex, age, height,body weight, body fat ratio, and other constants in advance, as well asa table of standard basal metabolism values per unit of surface area onthe body. These devices also use formulas for calculating the calorieexpenditure when the subject is at rest or is exercising. When measuringthe calorie expenditure, the measured pulse rate value and each of theconstants cited above are substituted into formulas according to whetherthe subject is resting or exercising. Calorie expenditure is thencalculated by referring to the aforementioned table of standard basalmetabolism values.

However, the conventional devices for measuring calories expendeddescribed above have the following problems.

First, these conventional calorie expenditure measuring devices areprovided with a comparison and determination device which determines thecalculation formula to be used by comparing the measured pulse rat e andthe "pulse rate threshold value (pulse rate when standing quietly)".However, it is well known that the pulse rate may rise due to variousfactors, including stress. Thus, since these devices determine thecalculation formula which will be used according to the pulse rate only,they cannot discriminate between whether an increase in the pulse rateis due to factors other than increased activity, such as stress, orbecause the subject is actually exercising. As a result, calorieexpenditure may be incorrectly calculated.

Second, in recent years it has come to be understood that there are avariety of physiological parameters, pulse rate included, that aresubject to cyclical variation (daily, monthly or annually). For thisreason, if the calculation of calorie expenditure is not corrected forthis variation, then the accuracy of the calculation is suspect.Conventional calorie expenditure measuring devices do not take intoconsideration the fact that pulse rate varies cyclically, so thataccurate measurement of calorie expenditure is difficult.

Thus, measurement accuracy of within 50 kcal as described above cannotbe obtained using these conventional calorie expenditure measuringdevices.

DISCLOSURE OF INVENTION

The present invention was conceived in consideration of theabove-described circumstances, and has as its first objective theprovision of a calorie expenditure measuring device which can accuratelydiscriminate between resting and active states, and which can calculatethe calorie expenditure with high accuracy by taking into considerationphysical and psychological effects as well as cyclical variation in thepulse rate.

Further, the present invention has as its second objective the provisionof a body temperature measuring device suitably employed in this calorieexpenditure measuring device which continuously measures a bodytemperature which is as close as possible to the subject's deep bodytemperature.

In order to achieve the above stated first objective, the presentinvention is firstly characterized in the provision of a basal metabolicstate specifying means for specifying the subject's basal metabolicstate; a correlation recording means for recording the correlationbetween the pulse rate and calorie expenditure; a correlation correctingmeans for correcting the correlation stored in the correlation storingmeans by using the basal metabolic state specified by the basalmetabolic state specifying means; and a calorie calculating means forapplying the subject's pulse rate in the correlation stored in thecorrelation storing means, to calculate the calorie expenditurecorresponding to this pulse rate.

In order to achieve the aforementioned second objective, the presentinvention is secondly characterized with the provision of a pulse wavedetecting means for detecting over a specific range the pulse pressurearound a site at which the subject's pulse is present; a temperaturedetecting means for detecting temperature, which is provided near thepulse wave detecting means; and a body temperature specifying means forspecifying the temperature which was detected at the site at which thelargest pulse pressure was detected from among the pulse pressures whichwere detected over the aforementioned specific region, as the bodytemperature.

As a result of the first characteristic described above, it is possibleto calculate the calorie expenditure per unit time with excellentaccuracy since the subject's psychological state, and of course hisresting or active state, are taken into consideration. Further, it isalso possible to more accurately determine calorie expenditure sincemonthly and annual fluctuations in the subject's state are taken intoconsideration.

Further, as a result of the above described second characteristic, thepulse pressure is detected over a specific area near where a pulse ispresent, and the temperature at the site where the pulse wave having thehighest pressure within this area was detected is measured as the bodytemperature. As a result, it is possible to measure at the periphery abody temperature which is stable and is as close as possible to the deepbody temperature. Moreover, once this measurement site is determined,continuous measurement is possible without any conscious recognition bythe subject.

BRIEF DESCRIPTION OF DRAWINGS

FIG. 1 is a block diagram showing the functional structure of thecalorie expenditure measuring device according to an embodiment of thepresent invention.

FIG. 2 is a block diagram showing the electrical structure of the samedevice.

FIG. 3A is a bottom view showing the outer appearance of the samedevice; FIG.

3B is a planar view thereof.

FIG. 4A is a partial cross-section perspective view of a portion of thisdevice in cross-section showing the structure of the device'stemperature sensor and pressure sensor;

FIG. 4B is a transparent perspective view of this part in cross-section.

FIG. 5 is a cross-sectional view showing an enlargement of theconnection between the elastic rubber in this pressure sensor and thesemiconductor substrate.

FIG. 6 is a block diagram showing a design in which a bias circuit hasbeen added to the pressure sensor.

FIG. 7 is a slant transparent view of a portion in cross-section showinganother structural example of the pressure sensor and temperaturesensor.

FIG. 8 is a view in cross-section of an essential component, providedfor explaining the theory of pulse wave detection using this pressuresensor.

FIG. 9 is a diagram showing the structure of the external devices whichcarries out the sending and receiving of information with the device.

FIG. 10A shows the regression formulas for resting and active stateswhich are used in the calculation of calorie expenditure in this device;

FIG. 10B is a diagram provided for explaining the correction of theregression formula in the device.

FIGS. 11A-11D are graphs showing the daily change in the rectaltemperature in several individuals during the spring, summer, winter andfall, respectively.

FIG. 12 is a table showing the standard basal metabolic values per unitarea of body determined separately according to age and sex.

FIG. 13 shows the external appearance of the site at which measurementsare conducted in an experiment to measure body temperature in theembodiment of the present invention.

FIG. 14A is a diagram showing the positions at which measurements weremade in this experiment, and the results of temperature measurements ateach of these site, when the area was dry;

FIG. 14B shows these results after the area was immersed in water.

FIG. 15 is a diagram provided for explaining the broad circulatorysystem of the human body.

FIG. 16 is a diagram showing arterial and venous branching in the microcirculatory system of the human body.

FIG. 17 is a flow chart showing the interrupt processing (1) which iscarried out in this device.

FIG. 18 is a flow chart showing the interrupt processing (2) which iscarried out in this device.

FIG. 19 is a diagram showing an example of the display in this device.

FIG. 20 is a diagram showing an example of the display in this device.

FIG. 21 is a diagram showing an example of the display in this device.

FIG. 22 is a diagram showing an example of the display in this device.

FIG. 23 is a flow chart showing interrupt processing (3) which iscarried out in this device.

FIG. 24 is a flow chart showing interrupt processing (4) which iscarried out in this device.

FIG. 25A is a bottom view of the external structure of the deviceaccording to another embodiment;

FIG. 25B is a planar view thereof.

FIG. 26 is a diagram showing the state of attachment of the device inanother embodiment.

FIG. 27A is a side view of the structure of the pulse wave detectoraccording to another embodiment;

FIG. 27B shows the state of attachment thereof.

FIG. 28 is a block diagram showing the structure for carrying outwavelet conversion of the pulse wave signal.

FIG. 29 is a block diagram showing the structure of the waveletconverter.

FIG. 30A is a diagram showing a one-beat component of a typical pulsewaveform;

FIG. 30B is a table showing the corrected pulse wave data thereof;

FIG. 30C is an example showing specific numerical values.

FIG. 31 is a diagram. provided to explain each of the positions on theupper arm and hip joint at which the pressure sensor and temperaturesensor can be attached.

FIG. 32 is a diagram showing the external structure of the device whenrendered into a necklace.

FIG. 33 is a diagram which explains the arrangement in which thepressure sensor and temperature sensor are attached to the carotidartery.

FIG. 34 shows the external appearance when the device is rendered as apair of eyeglasses.

FIG. 35 shows the external appearance when the device is rendered as apocket card.

FIG. 36A shows the external appearance when the device is rendered as apedometer;

FIG. 36B shows the state of attachment thereof.

FIG. 37 shows an example of the display of the device when showing thechange over time in the subject's deep body temperature.

FIG. 38 shows the relationship between the heartbeat waveform in anelectrocardiogram and the RR interval obtained from this waveform.

FIG. 39A shows the waves which make up the changes in blood pressure;

FIG. 39B shows the results of spectral analysis of blood pressurevariation.

FIG. 40 shows an example of the display in this device.

FIG. 41 shows the results of spectral analysis of the pulse waveform.

FIG. 42 shows the change in the heart rate with respect to the change inthe environmental temperature.

BEST MODE FOR CARRYING OUT THE INVENTION

Preferred embodiments of the present invention will now be explained.

1: Theoretical Basis for Calculation of Calorie Expenditure

The theoretical basis for the first embodiment will now be explained. Ingeneral, there is a curved line relationship between pulse rate and theoxygen intake quantity, such as shown by the solid line in FIG. 10A.

With respect to the relationship between the quantity of oxygen consumedand the calorie expenditure, even if a coefficient of 4.85 kcal perliter of oxygen is consistently used, such as disclosed on page 206 in"Calculation of daily energy expenditure by diary profile of heart-rate"in the Employees' Pension Plan Hospital Annual Report No. 17, 1990, thisdoes not lead to a large error. For this reason, provided that the pulserate per unit time (beats/min) is known, then the quantity of oxygenconsumed may be understood by referring to the correlations shown inthis figure. If this is multiplied by the aforementioned coefficientvalues, then the calorie expenditure per unit time can be calculated. Inother words, the correlation shown in the figure actually shows therelationship between pulse rate and calorie expenditure.

Next, the correlation shown in FIG. 10A is determined by measurement foreach subject in advance. A design may be provided in which the thusobtained correlations are stored in table form, for example. In view ofthe fact that the change in the amount of oxygen consumed in the regionwhere the pulse rate is low is small, while the change in the amount ofoxygen consumed in the region where the pulse rate is high is large,however, a design is also acceptable in which the aboved-describedrelationship is divided into "aresting" and "active", and the respectiverelationships are expressed using linear regression formulas.

The method disclosed in Hirosaki Medicine Journal 40(1): 60-69, 1988,"Study on estimating energy expenditure by heart rate," may be used as amethod for obtaining the correlation for a subject. Namely, the oxygenintake quantity during basal metabolism, such as when sleeping, may bemeasured using an ordinary method employing a Douglas bag, and may bemeasured when the subject is at rest or exercising using a commerciallyavailable respiration analyzer or the like. Further, when carrying outmeasurements after applying an exercise load on the subject, it isacceptable to wait for the subject's pulse rate and oxygen intakequantity to become constant, and then to gradually increase the exerciseload using a treadmill or the like.

In this way, the correlation between calorie expenditure and the pulserate corresponding to the subject is obtained in advance. Specifically,when using "resting" and "active" linear regression formulas, theinformation (slope, y-intercept of the regression line, etc.) for eachregression formula is determined in advance.

Additionally, the regression formulas for the correlation present in thecurved line relationship can be complicated, or may require much memoryeven if rendered into table form. In view of these disadvantages, thepresent embodiment incorporates a design which employs a "resting" and"active" linear regression formulas. The present invention is notlimited thereto, however, but may employ a correlation which is presentin the curved line relationship.

However, it is known that pulse rate may rise due to a variety offactors such as stress and the like. Accordingly, if a design isemployed in which a regression formula is selected which is appropriateaccording to the detected pulse rate, then it is not possible todetermine whether the rise in pulse rate is due to a factor other thanactivity, such as stress, or is due to activity performed by thesubject. Thus, calorie expenditure may be incorrectly calculated.

Accordingly, as a general rule, the present embodiment employs a"resting" regression formula when the subject is at rest, and employs an"active" regression formula when the subject is in a state of activity.However, if the pulse rate and body temperature are high even when thesubject is in a state of rest, then it is possible that the subject hasjust suspended activity, or that an abnormal condition exists. For thisreason, as an exception in the embodiments, the "active" regressionformula is used when the subject's pulse rate and body temperature arehigh, even though the subject is in a state of rest.

By selecting the regression formula in response to the subject's restingor active state, and applying the pulse rate in that regression formula,it is possible to calculate calorie expenditure per unit time withexcellent accuracy.

On the other hand, physiological conditions such as body temperature andpulse rate not only change over the course of one day, but are alsoknown to change over longer periods of time (one month or one year, forexample). When these changes are compared, the change over the course ofone day (hereinafter, referred to as "daily change") starts from andthen returns to a standard value. Change over one month or one year(hereinafter, referred to as "monthly change" or "annual change") ischange in the standard value itself over the passage of days.

The annual change in rectal temperature (body temperature) will beexplained here as one example of annual changes in physiologicalconditions. FIGS. 11A-11D are graphs showing the change over one day inrectal temperature in a plurality of subjects, for spring, summer, falland winter, respectively. As is clear from these figures, a humanbeing's rectal temperature (body temperature) and the standard valuethereof changes over the course of one year. The same may be said of thepulse rate, with its standard value also viewed to change over thecourse of one year.

However, the pulse rate at the subject's basal metabolic state in FIG.10A is the value for obtaining the correlation, i.e., is a value whichis limited to a specific time period. For this reason, setting thisvalue as the base for the correlation does not take into considerationthis type of monthly and annual change, and is thus a cause of errorwhen calculating calorie expenditure.

Therefore, in this embodiment, the basal metabolic state is specifiedafter continuously measuring the subject's deep body temperature, thepulse rate thereof is obtained, and the correlation is corrected aftermatching it to monthly and annual change in the subject's condition. Inother words, this embodiment provides a design in which the informationfor each of the linear regression formulas is corrected by matching itto monthly and annual change in the subject's condition.

By taking this cyclical change in pulse rate into consideration in thisway, it is possible to calculate calorie expenditure with excellentaccuracy.

2: Embodiment

Drawing on the theoretical basis explained above, the calorieexpenditure measuring device according to the embodiment of the presentinvention will now be explained.

2-1: Functional structure

The functional structure of the calorie expenditure measuring deviceaccording to the present invention will now be explained. FIG. 1 is ablock diagram showing this functional structure.

In this figure, body motion detector 101 is a sensor for detecting bodymotion when the subject is exercising. It may be formed of anacceleration sensor, for example. The body motion signal from this bodymotion detector 101 is converted to a digital signal by A/D converter102. FFT (fast Fourier transform) processor 103 uptakes over a specificinterval of time the body motion signal which has been digitallyconverted, and executes FFT processing. Body motion determining element104 determines whether the subject is in a state of rest or activity(exercise), based on the results of FFT processing. As a method for thisdetermination, a method may be employed in which a determination is madeas to whether or not the highest amplitude level of the frequencycomponent has exceeded a threshold value, with the subject judged to bein a resting state when the result of this determination is negative, orto be in a state of activity when the result of this determination ispositive.

Pulse wave detector 111 is a sensor which detects the subject's pulsewave. The pulse wave signal from pulse wave detector 111 is converted toa digital signal by analog to digital (A/D) converter 112. FFT processor113 then uptakes the digitally-converted pulse wave signal over aspecific period of time, and carries out FFT processing. The pulse rateis then determined from the FFT-processed pulse wave signal by pulserate calculator 114. Note that pulse rate calculator 114 can calculatethe pulse rate by determining the peak intervals of the pulse waveformtaken up, and taking the inverse thereof. This will be explained below.Further, it is necessary to obtain the heartbeat rate, i.e., the numberof beats of the heart per unit time, for this embodiment. However, sincethe heartbeat rate equals the pulse rate, a design in which pulse rateis determined is acceptable. Accordingly, it is acceptable to employ adesign wherein the heartbeat is directly obtained by detecting theelectrocardiogram. While a distinction is made between the pulse rateand the heart rate from a medical perspective, there is no reason to doso in the present invention. Thus, hereinafter, both heart rate andpulse rate will be referred to as "pulse rate".

Next, body temperature detector 121 measures the subject's deep bodytemperature (or the body temperature which is sufficiently closethereto) by means of the principles and designs described below. Bodytemperature detector 121 outputs an analog signal corresponding to themeasured value of the temperature as the body temperature signal. Thebody temperature signal from body temperature detector 121 is convertedto a digital signal by A/D converter 122 and output.

Deep body temperature is useful in specifying the subject's basalmetabolic state. It may, however, differ from the general bodytemperature (obtained inside the mouth or under the arm, for example)depending on the external temperature, evaporation of sweat from thebody surface or the like. The present embodiment employs a design inwhich a suitable regression formula is selected after taking intoconsideration movement and body temperature, as well as the pulse ratewhen calculating calorie expenditure. In this case, however, the bodytemperature employed is the general body temperature. Accordingly, whenusing the deep body temperature detected by body temperature detector121 as the general body temperature, some sort of correction must becarried out. For the purpose of this correction, the relationshipbetween deep body temperature and general body temperature may berendered into table form in advance, and stored in RAM 203, for example,with the detected deep body temperature used after converting it to ageneral body temperature.

Next, basal metabolic state specifying element 131 specifies thesubject's basal metabolic state from the FFT-processed pulse wave signalusing a method which will be explained below, and outputs the pulse ratefor this state.

Subject information recording element 141 records the subject's weight,height, sex and age which are set using switches Sw1, Sw2 and anexternal device which will be explained below.

Basal metabolism calculator 142 stores the table shown in FIG. 12 (basalmetabolism standard values per unit body surface area, Ministry ofHealth announcement, 1969), and determines the subject's basalmetabolism by carrying out the following calculations.

Namely, first, basal metabolism calculating element 142 determines thebody surface area A [m² ] from body weight W [kg] and body height H [cm]stored in subject information recording element 141 using the followingformula.

    Body surface area BSA=body weight W.sup.0.425 ×body height H.sup.0.72 ×7.184×10.sup.-3

For example, the average Japanese male, age 24, has a height of 1.65 [m²], while the average Japanese female, age 24, has a height of 1.44 [m²].

Second, basal metabolism calculator 142 determines the basal metabolismstandard values corresponding to the age and sex of the subject whichare stored in subject information recording element 141 by referencingthe aforementioned table. For example, in the case of a 24-year oldJapanese woman, the basal metabolism standard value is determined to be34.3 [kcal/m² /hour].

Third, basal metabolism calculator 142 calculates the subject's basalmetabolism according to the following formula.

    Basal metabolism [kcal/hour]=body surface area BSA×basal metabolism standard value

The explanation will now return to FIG. 1. Correlation recording element151 stores the correlation between the calorie expenditure and the pulserate obtained for the subject, and outputs this information. In thisembodiment, correlation recording element 151 stores the information forboth the regression formulas for each of the resting and active states(see FIG. 10A), and outputs the information for the regression formulaselected by regression formula selecting element 153. The correlationstored in correlation recording element 151 is input via switches Sw1,Sw2, an external device, or the like, which will be explained below.

Correlation correcting element 152 corrects the correlation stored incorrelation recording element 151 from the pulse rate at the subject'sbasal metabolic state specified by basal metabolic state specifyingelement 131 and from the subject's basal metabolism determined by basalmetabolism calculator 142.

Specifically, with respect to the correlation stored in correlationrecording element 151, correlation correcting element 152 carries out aparallel shift of uncorrected standard point P expressing the basalmetabolic state, to standard point P' which is determined according tothe pulse rate at the subject's specified basal metabolic state and thesubject's basal metabolism. Second, correlation correcting element 152rewrites the correlation stored in correlation recording element 151 tothe correlation after the parallel shift. As a result, the correlationstored in correlation recording element 151 is corrected to matchmonthly and annual changes in the subject's condition. Thus, in thisembodiment, the information for each linear regression formula isupdated.

FIG. 10B shows a parallel transition in the x direction only. However,if the age, height or weight change, then the basal metabolism willnaturally also change. In this case, correction is carried out by aparallel shift in the y direction as well.

Regression formula selecting element 153 first determines the high andlow for body temperature by comparing the body temperature and thethreshold value, for example. Second, regression formula selectingelement 153 determines the high and low pulse rate by comparing thepulse rate and its threshold value. Third, regression formula selectingelement 153 selects the regression formula which should be used for thecombination of these high and low values and the presence or absence ofbody motion. Specifically, regression formula selecting element 153selects the "active" regression formula in the case of (1) and (2)below, and selects the "resting" regression formula in the case of (3)and (4) below.

    body motion present                                        (1)

    body motion absent, pulse high, body temperature high      (2)

    body motion absent, pulse high, body temperature low       (3)

    body motion absent, pulse low                              (4)

Note that "body temperature" as used here refers to general bodytemperature, as explained above.

Case (2) above, in which the "active" regression formula is used, isprovided for the exceptional times when the subject's body is in anabnormal state or when the subject has just suspended activity. Case(3), when the subject's pulse rate is high, body motion is absent, andthe body temperature is low, is viewed to be due to psychologicalfactors, so that a "resting" regression formula is used. As a result,the present embodiment enables a more accurate calculation of calorieexpenditure as compared to the conventional technology in which aregression formula is simply selected using only the high and low valuesfor pulse rate.

When separating the correlation into "resting" and "active", as in thisembodiment, it is necessary to select the regression formulas accordingto the subject's state. For this reason, a region OP1 is provided. If,however, a curved line regression formula or a table is employed, thenthis structure is not needed.

Next, oxygen intake quantity calculator 161 applies the pulse rateobtained from pulse rate calculator 114 to the correlation stored incorrelation recording element 151, and determines the actual oxygenintake quantity. In this embodiment, the oxygen intake quantity isdetermined after applying the regression formula selected by regressionformula selecting element 153. Calorie expenditure calculator 162multiplies the obtained oxygen intake quantity by the coefficient 4.85[kcal/l], and calculates calorie expenditure per unit time.

Recording element 163 sequentially stores the calculated calorieexpenditure. Notifying element 164 carries out notification based on thecalculated calorie expenditure and the stored contents of recordingelement 163.

Controller 170 controls the operation of all parts.

2-1-1: Principle for measurement of deep body temperature

The principle for measuring body temperature in this embodiment will nowbe explained. The present inventors carried out experiments using aradiation thermometer having an aperture diameter of around 5 mm tomeasure the temperature distribution around the area of the radialartery. The temperature roughly directly above the radial artery wasjust less than 1° C. higher than the surrounding area, so that a bodytemperature close to normal was measured. The details and results of theexperiments performed by the present inventors will now be explained.

FIG. 13 shows an external view of the site at which measurements weremade. The measurement of temperature was carried out along an imaginaryline intersecting with the radial artery/ulnar artery when moving fromthe radial styloid process toward the heart 10 mm at a time. As shown inFIGS. 14A and 14B, measurement points were provided at 5 mm intervalsalong this line. The results of temperature measurements at each ofthese points is as shown in this figure. FIG. 14A shows the experimentalresults when the arm is dry, while FIG. 14B shows the experimentalresults when temperature measurements where carried out after themeasurement site was immersed in water once. As is clear from theseresults, the temperatures above the radial and ulnar arteries are bothhigher than the surrounding area, with the values being close to deepbody temperature. Moreover, the difference in the temperature above anartery and the temperature of the surrounding area is expressed evenmore clearly after immersion in water. Specifically, the temperaturemeasured above the radial artery is not effected by immersion in water,but is nearly the same as when the arm is dry.

From a medical perspective, this phenomenon can be explained by the factthat the radial artery and other arteries carry blood, which is a heatsource. Accordingly, the surface skin temperature directly above theartery is viewed to be sufficiently close to the deep body temperature,as compared to the temperature of the surrounding area. In addition, apulse is observed directly above the radial artery which has a fast timeresponse accompanying the output of blood from the heart. Accordingly,by finding the area in which the pulse is generated and measuring thetemperature at that site, it is possible to obtain a body temperaturewhich is sufficiently close to deep body temperature.

From the perspective of anatomy, any area is appropriate as a pulsedetection site, provided that it is directly above an artery (such asthe aorta, medium and small arteries) which is not extremely small. Forexample, the radial artery may be cited in the case of a site along amedium-sized artery, while the trunk of the finger is appropriate in thecase of a small artery.

The "broad circulatory system" refers to the blood pathways named fortheir physical locations which distribute blood from the heart to allparts of the human body and which return the blood from those parts.FIG. 15 is provided to explain the arrangement of the broad circulatorysystem. In contrast, the micro circulatory system refers to circulatoryunits which include microscopic blood vessels which provide exchangebetween body fluids and tissues, lymphatic capillaries which accompanythese, and the interstitium and actual tissue which surround these. Asshown in FIG. 16, in the micro circulatory system, micro arteries branchinto a network of capillary vessels at the ends of the arterial system,and then again congregate to form micro veins which connect to veins.

Thus, even when measuring body temperature at the radial artery or otherperipheral area, it is possible to measure a body temperature which isclose to deep body temperature with considerably good accuracy evenafter the site has been immersed in water, provided that the site issubject to normal conditions and not some unusual circumstance such asconstantly soaking in water. For example, when considering anapplication which examines the change in body temperature when a personis sleeping, body temperature can be measured without any problems inaccordance with the measurement principles described above.

Assuming the above-described principle to be true, the present inventionmeasures a body temperature which is sufficiently close to the subject'sdeep body temperature by disposing a temperature and pressure sensorabove the subject's radial artery, and taking the temperature detectedat this site as the subject's body temperature.

It has been the conventional practice to measure deep body temperatureby measuring the temperature rectally, or under the tongue or armpit.However, these devices are currently comprised of table-top equipment,while the measurement obtained at these sites was only for a singlepoint in time. Further, these devices were typically large, so that itwas not possible to carry them about in a portable fashion so that bodytemperature could be constantly measured.

In contrast, the present embodiment enables the measurement of a bodytemperature which is sufficiently near deep body temperature to becarried out comparatively simply. For this reason, a body temperaturemeasured in this embodiment which is sufficiently close to the subject'sdeep body temperature is not only useful in the calculation of calorieexpenditure, but is by itself extremely significant from the perspectiveof clinical medicine.

Accordingly, a design in which the subject or a third party is notifiedof the obtained deep body temperature itself, or the result ofprocessing thereof, is also significant. This design will be explainedbelow.

2-1-2: Specification of basal metabolic state

Next, the specification of the subject's basal metabolic state which isperformed by basal metabolic state specifying element 131 of the presentembodiment will be explained.

First, basal metabolic state specifying element 131 supposes a sedateperiod when specifying the subject's basal metabolic state. This sedateperiod is that time period during the day when the physiological stateis closest to the basal metabolism. Ordinarily, this would be duringdeep sleep, and excludes REM sleep or prior to waking. Accordingly, inthis embodiment, the deep sleep interval is first specified. Theintensity of body movement (acceleration level) is clearly less in deepsleep than in REM sleep or prior to waking. Accordingly, the intervalduring which the acceleration level based on the body motion signal isbelow a threshold value can be specified as the deep sleep interval.

Moreover, ordinarily, this type of deep sleep interval is considerablylonger than the sedate period which is being determined. As discussedabove, physiological state changes on a daily cycle, such that thestandard value can only be obtained during a small interval of time.Accordingly, when the sedate period is taken as a long period of time onthe order of the deep sleep interval, then the representative valueduring this interval may differ greatly from the standard value. Inother words, the sedate period should be determined by specifying thedeep sleep interval more precisely. Thus, in this embodiment, a sedateperiod which is sufficiently short is obtained by monitoring changes inbody temperature.

In general, body temperature is known to follow daily change, with thecurve thereof shifting from descending to ascending to match basalmetabolic state. Thus, in this embodiment, the curve for bodytemperature during the interval when measurements were made is obtained.When, from among the inflection points along the curve, an inflectionpoint at which a minimum value is obtained is within the deep sleepinterval, then a specific time interval around the inflection point isspecified as the sedate period. The curve for body temperature can beobtained using a conventional method (least squares method, for example)to determine the formula for the curved line which most closely fitseach point specified by the body temperature input during the specifictime interval and each time of input.

Note that it is also acceptable not to consider the deep sleep interval,but to specify the specific time period around an inflection point atwhich a minimum value was obtained along the curve for the bodytemperature as the sedate period. However, since the inflection point atwhich a minimum value is obtained may appear outside the deep sleepinterval depending on the state of use or the subject's biorhythms, thisembodiment employs both the deep sleep interval and the body temperaturecurve. Further, when the threshold value which becomes the standard fordetermining the deep sleep interval is set to be sufficiently small, sothat the deep sleep interval is sufficiently short, then it is possibleto use the deep sleep interval as is for the sedate period.

Further, when detecting physiological information obtained during asedate period specified in this way, the physiological information isthe value which should be the standard for monthly and annualphysiological change. As in the case of the deep body temperature, thisphysiological information is not only useful in the calculation ofcalorie expenditure, but is also extremely significant by itself.

Accordingly, a design which notifies the subject or a third party of thephysiological information obtained during the sedate period, or theresult of processing thereof, is naturally significant. This design willbe described below.

2-2: Electrical structure

Next, the electrical structure for realizing the functional structureshown in FIG. 1 will be explained. FIG. 2 is a block diagram showingthis structure.

CPU 201 carries out control of various parts via bus B, as well asexecuting various processing and calculations based on basic programsstored in ROM 202. CPU 201 corresponds to the FFT processors 103,113,body motion determining element 104, pulse rate calculator 114, basalmetabolic state specifying element 131, basal metabolism correctingelement 142, correlation correcting element 152, regression formulaselecting element 153, oxygen intake quantity calculator 161, calorieexpenditure calculator 162, and controller 170.

RAM (random access memory) 203 stores the measured value of each of thesensors which will be explained below, and the results of thecalculations. It corresponds to the operational area when CPU 201 iscarrying out calculations, is employed as a storage area for targetvalues, and corresponds to subject information recording element 141,correlation recording element 151 and recording element 163 shown inFIG. 1.

Switch interface 204 detects the operational state of switches Sw1 andSw2, and informs CPU 201 to that effect. These switches may be providedin a portable device such as a wristwatch. Switch Sw1 is used toindicate the start or stop of measurement of calorie expenditure. SwitchSw2 is used to select the various functions (modes).

Display 205 is provided on a portable device such as a wristwatch, inthe same manner as switches Sw1, Sw2. It displays various informationunder the control of CPU 201, and is, for example, formed of an LCD(liquid crystal display panel). Alarm 206 sounds an alarm under thecontrol of CPU 201, in order to notify the subject of a change in thevarious states. Display 205 and alarm 206 correspond to notifyingelement 164 in FIG. 1. Further, I/O interface 207 has an LED and aphototransistor, and is for sending and receiving information with anexternal device.

Watch circuit 208 has the functions of an ordinary wristwatch, as wellas the functions for carrying out various interrupt processing bysending an interrupt signal to CPU 201 at time intervals determined inadvance. For this reason, CPU 201 can read out the current time fromwatch circuit 208.

Body motion sensor interface 209 samples the body motion signal frombody motion detector 101 at specific intervals, and outputs the bodymotion signal after digitally converting it. Body motion sensorinterface 209 corresponds to A/D converter 102 in FIG. 1.

Pressure sensors Ps1˜Ps6 are sensors for measuring the pulse pressurearound the subject's radial artery. They output the analog electricalsignal which corresponds to the pulse pressure at this area as a pulsewave signal, and together correspond to pulse wave detector 111.Pressure sensor interface 210 samples the pulse wave signals frompressure sensors Ps1˜Ps6 at specific time intervals, and outputs thepulse wave signal after digitally converting it. It corresponds to A/Dconverter 112 in FIG. 1.

Temperature sensors Ts1˜Ts6 are disposed about pressure sensors Ps1˜Ps6,and each measure the temperature of the skin surface around the radialartery. The analog electrical signal corresponding to the measured valueof the temperature is output as the body temperature signal. Temperaturesensors Ts1˜Ts6 together correspond to body temperature detector 121shown in FIG. 1. Temperature sensor interface 211 samples the bodytemperature signals from temperature sensors Ts1˜Ts6 at specific timeintervals, and outputs them after conversion to a digital signal. Itcorresponds to A/D converter 122 in FIG. 1. A temperature sensor whichemploys thermocouples is preferably used from the perspective ofconversion efficiency. However, it is also acceptable to use atemperature sensor which employs temperature characteristics likereverse current, such as a thermoelement like a thermocouple,thermister, diode, transistor, or the like.

2-3: External structure

In this way, the present embodiment employs a combination of pressuresensors Ps1˜Ps6 and temperature sensors Ts1˜Ts6. The external appearanceof the device will now be explained with reference to FIG. 3.

FIG. 3A is a bottom view of the calorie expenditure measuring deviceaccording to this embodiment. Switches Sw1 and Sw2 have been provided tothe side of device main body 300 which is designed in the form of awristwatch. Pressure sensors Ps1˜Ps6 and temperature sensors Ts1˜Ts6 arealigned in a row along the longitudinal direction of band 301.

More specifically, pressure sensor Psi (i=1˜6) and temperature sensorsTsi (i=1˜6) are disposed about the direction of the width of band 301.These pressure sensors Psi and temperature sensors Tsi form pairs. Band301 wraps around the wrist of the subject, so as to be in tight contactwith the surface of the skin around where the radial artery runs.

FIG. 3B is a planar view of the calorie expenditure measuring deviceaccording to this embodiment. A display 205 is provided to the uppersurface thereof. An LED which serves as a transmission element and aphototransistor which serves as a receiving element are provided todevice main body 300 for carrying out optical transmission with anexternal device to be explained below (LED and phototransistor notshown).

2-4: Detailed Structure of Temperature Sensor and Pressure Sensor

An example of the specific structure of the temperature sensor andpressure sensor will now be explained. The sensor discussed below is onedeveloped by the present inventors and corresponds to the pressuresensor disclosed in Japanese Patent Application, Laid Open No. Hei6-10144 (Title of the Invention: Pressure sensor, and pressure vibrationdetection device and pulse wave detection device employing said sensor).

FIG. 4 shows the structure of the temperature and pressure sensorsaccording to the present invention. FIG. 4A is a partial cross-sectionalperspective view of the pressure sensor in cross-section; and FIG. 4B isa transparent perspective view of the pressure sensor in cross-section.The sensor shown in these figures correspond to one pair consisting ofpressure sensor Ps1 and temperature sensor Ts1 shown in FIGS. 2 and 3,for example.

In FIG. 4A and 4B, pressure sensor 60 is formed from pressure sensitiveelements S1˜S4 and semispherical elastic rubber 61. The shape of elasticrubber 61 is taken to be a perfect semisphere hereinafter. Pressuresensitive elements S1˜S4 are disposed to the lower surface L of elasticrubber 61, and respectively output as detected signals voltages V1˜V4which are proportional to the detected pressures. The (x, y) coordinatesof detection positions Q1˜Q4 of these pressure sensitive elements S1˜S4are (a,0), (0,a), (-a,0), and (0,-a) respectively, when the radius ofelastic rubber 61 is r, the center of the lower surface L is the origin(0,0), and r>a>0. Namely, the coordinates at which pressure is to bedetected by pressure sensitive elements S1˜S4 are on the x and y axes onthe lower surface L and are separated from the origin by an equaldistance a.

Temperature sensor 62 is formed of a thermocouple, and is disposed atthe center (i.e., origin) of lower surface L. Lead wires 80,80 which areconnected to the leads of the thermocouple are connected to temperaturesensor interface 211 of FIG. 2. As shown in FIG. 4A or 4B, whentemperature sensor 62 is disposed in the same plane as pressuresensitive elements S1˜S4, then an accurate temperature measurement inthe tissues above the arteries can be realized when measuring the bodytemperature. Further, the area occupied by temperature sensor 62 onlower surface L is preferably designed to be less than the surface areaoccupied by each of the pressure sensitive elements S1˜S4 on lowersurface L. Thus, if the area occupied by temperature sensor 62 is small,the thermoelectric exchange efficiency improves by that amount.

Next, with reference to FIG. 5, joining between each of the pressuresensitive elements and elastic rubber 61 will be explained usingpressure sensitive element S1 as an example. As shown in this figure,semiconductor substrate 63 is adhered to lower surface L of elasticrubber 61 by means of adhesive layer 64 which has an elastic quality. Inaddition, pressure sensitive element S1 which detects pressure atdetection position Q1 is formed in semiconductor substrate 63 togetherwith hollow chamber 65₋₁ which opens on the detection position. Pressuresensitive element S1 is formed from thin element 66₋₁ which is 20 to 30μm in thickness and which is employed as a diaphragm, and fromdistortion gauge 67₋₁ which is formed to the surface of thin element66₋₁.

Pressure-sensitive element S1 is formed using a known technique foretching semiconductors. In particular, distortion gauge 67₋₁ is formedof a piezo resistance element (p-type resistance layer) which is formedusing a selective dispersion technique for impurities (i.e., boron,etc.). When this type of distortion gauge 67₋₁ bends, the resistancevalue varies in response to the distortion.

Similarly, pressure-sensitive elements S2˜S4 are formed on top ofsemiconductor substrate 63, with the resistance values thereof varyingrespectively in proportion to the pressure at detection positions Q2˜Q4.

When a pressure vibration is generated on the semispherical surface ofelastic rubber 61 in a pressure sensor 60 of the above describedstructure, it is propagated as an elastic wave through elastic rubber61, and becomes microvibrations at detection position Q1. causing achange in the pressures inside hollow chambers 65₋₁. In this case,distortion gauge 67₋₁ bends under the difference between the pressureinside hollow chamber 65₋₁ and the outside pressure introduced byopening 68₋₁ which is open to the outside environment. As a result, theresistance value changes in response to the pressure vibration. Aluminumelectrodes (not shown) for directing the external circuits are depositedto each end of distortion gauges 67₋₁ -67₋₄. The electrodes can berespectively converted between resistance and voltage by means of thecircuit described below, with the voltage output as a detected voltageV1˜V4 proportional to the pressures at detection positions Q1˜Q4.

Next, the electrical connection between pressure sensitive elementsS1˜S4 and the bias thereof will be explained with reference to FIG. 6.In this figure, distortion gauges 67₋₁ to 67₋₄ are all shown asequivalently variable resistors. As shown in this figure, each ofdistortion gauges 67₋₁ to 67₋₄ corresponding to pressure sensitiveelements S1˜S4 are connected in series, with output terminal 69, . . . ,69 provided to the respective ends thereof. Both ends of the distortiongauges 67₋₁ to 67₋₄ series are connected to bias circuit 70.

This bias circuit 70 is formed of constant-current circuit 71, switch 72which turns on and off the output signal from constant-current circuit71, and switching circuit 73 which turns switch 72 on when controlsignal T is at a high level. The device is designed so that when controlsignal T is at a high level, the output signal from constant currentcircuit 71 is impressed on distortion gauges 67₋₁ to 67₋₄. Theresistance value of the distortion gauge changes in response to bendingas described above, so that when the same fixed current flows thougheach of distortion gauges 67₋₁ to 67₋₄, the voltages V1˜V4 betweenoutput terminals 69, . . . 69, are proportional to the pressures atdetection positions Q1˜Q4, and relatively indicates the size of thatpressure.

An embodiment such as shown in FIG. 7 may also be considered as anotherexample for realizing the provision of a temperature sensor in elasticrubber 61. This embodiment employs a thermocouple array for temperaturesensor 62. A circular opening 81 is provided in elastic rubber 61, whilea cylindrical waveguide 82 is punched through elastic rubber 61 havingas a center axis the lead wire which passes through temperature sensor62. As a result, temperature sensor 62 receives the energy radiated fromthe body which is opposite elastic rubber 61, and measures thetemperature. The diameter of cylindrical waveguide 82 is roughly twicethat of temperature sensor 62. As one variation of the embodiment shownin FIG. 7, a design may also be considered in which an optical meanswhich collects light, such as a lens system, is provided along waveguide82.

Next, the principle for measuring the pulse wave using pressure sensor60 will be explained. Note that the arteries which are discussed belowall pass through the skin surface. As shown in FIG. 8, the semisphericalside of elastic rubber 61 is pressed in the vicinity of artery 75. Avibration occurs at point Pn on the semispherical surface of elasticrubber 61 due to a pressure vibration wave (i.e., pulse wave) generatedfrom artery 75. In this discussion, point Pn is assumed to be thevibrational center. The vibration is propagated through elastic rubber61, detected by pressure-sensitive elements S1˜S4 as a detection signalhaving electrical signals (i.e., voltages V1˜V4) indicating pulse waves,and output. Note that in FIG. 8, numeral 76 indicates subcutaneoustissue of the arm.

The pressure sensor interface 210 shown in FIG. 2 samples the voltagesV1˜V4 detected by pressure sensitive elements S1˜S4, carries out A/D(analog/digital) conversion, and relays the converted voltages to bus B.In this explanation, the four voltages V1˜V4 undergo A/D conversion,however, it is also acceptable to convert any number of voltages. CPU201 selects the largest of these voltages, and carries out A/Dconversion on one of these.

2-5: External device

Next, the external device which carries out sending and receiving ofinformation with the device of the present invention will now beexplained with reference to FIG. 9. As shown in this figure, theexternal device is formed of a device main body 600, display 601, keyboard 602, printer 603 and the like. It is equivalent to an ordinarypersonal computer, with the exception of the following points.

Namely, device main body 600 internally houses an optical interfaceconsisting of a transmission controller and a receiving controller,which are not shown in the figures, for sending and receiving data bymeans of optical signals. The transmission controller is provided withLED 604 for sending optical signals, and the receiving controller isprovided with a phototransistor 605 for receiving optical signals. Thedevices employed for LED 604 and phototransistor 605 havecharacteristics which are the same or very similar to thecharacteristics of the LED and phototransistor provided to device mainbody 300 of the calorie expenditure measuring device. A device employingnear infrared (having a central wavelength of 940 nm) is preferable, forexample. When employing a device which uses near infrared, a visiblelight cutting filter for blocking visible light is provided to the frontsurface of device main body 600, forming a transmission window 606 fortransmitting optical communications.

Information is sent and received between an external device such asdescribed above and the device main body 300 of the calorie expendituremeasuring device by means of optical communications. The details of thesending and receiving of information will be explained together with theoperation of the device.

While the present embodiment carried out the communications functions bymeans of optical communications, a variety of other arrangements may beconsidered such as wireless communications using electric waves or wiredcommunications via cables.

2-6: Operation

The operation of the calorie expenditure measuring device according tothe present embodiment will now be explained.

Device main body 300 has the structure of a wristwatch, and thereforehas the functions of a wristwatch in addition to functions for measuringcalorie expenditure. However, since the wristwatch functions do notdirectly relate to the present invention, the following explanation willfocus mainly on functions associated with the measurement of calorieexpenditure.

First, the subject tries to wear device main body 300 whenever possible,provided it is not inconvenient, and depresses switch Sw1 when it isnecessary to know the calorie expenditure. CPU 201 recognizes thedepression of the switch via switch interface 204, sequentially readsout pulse wave signals from pressure sensors Ps1˜Ps6 via pressure sensorinterface 210, and stores these in RAM 203.

Once the intake processing is completed, CPU 201 selects the maximumvalue from among the six measured values for pressure, and specifies thepressure sensor at which the maximum pulse pressure was measured.Thereafter, this specified pressure sensor, and its matching temperaturesensor are employed for measurements.

2-6-1: Specification of basal metabolic state

Next, the operation to specify the basal metabolic state in thisembodiment will be explained. Note that the following processingpresupposes that the subject's body weight, height, sex, age andcorrelations (information of each linear regression formula) have beenpreset in RAM 201 (i.e., subject information recording element 141 andcorrelation recording element 151) using Sw1, Sw2 (or the externaldevice). This correction is carried out daily during the measurementintervals which have been preset (i.e., the interval during which thesubject's state is closest to his basal metabolic state).

First, when the current clock time according to watch circuit 208indicates that it is time to begin measurements, CPU 201 continuouslyinputs a body motion signal from body motion detector 101 via bodymotion sensor interface 209. In this embodiment, the initial value ofmeasurement start time S and measurement end time E are set to 2:00 and6:00, respectively, and have been stored in ROM 202 in advance. This isbecause, in the case of a healthy person, the sedate state reachedduring the time period from 2:00 to 6:00 when active metabolism declinesthe most is known as the daily change in body temperature, bloodpressure, pulse rate, and the like.

Based on the body motion signal input during the measurement interval,CPU 201 detects the time at which the subject's acceleration is belowthe threshold value, and the time at which the acceleration firstexceeds the threshold value after the aforementioned time, and specifiesthe time interval enclosed by these two points as the deep sleepinterval.

Next, during the specified deep sleep interval, CPU 201 inputs the bodytemperature signal from body temperature detector 121 at specific timeintervals via temperature sensor interface 211, and writes the obtainedbody temperature in RAM 203 in association with the input times. Inparallel with this operation, CPU 201 determines the pulse rate byinputting the pulse wave signal from pulse wave detector 111 during thespecified deep sleep interval at specific time intervals via pressuresensor interface 210, and stores these in association with the inputtimes in RAM 203.

It is acceptable to create an association between the input time and theaddress of RAM 203 in advance, and then write the various data in theaddress corresponding to the input time, or to express data other thanthat initially measured in the form of a difference from the immediatelypreceding data. As a result, it is possible to reduce the amount of datastored in RAM 203.

When the deep sleep interval is not sufficiently long, i.e., when thedeep sleep interval does not satisfy the duration required for thesedate period, then CPU 201 erases the data written in RAM 203 duringthe aforementioned deep sleep interval, and continues processing todetect a deep sleep interval.

Next, when the current time as detected by watch circuit 208 reaches thetime at which measurements are to be concluded, then CPU 201 determinesthe curve from the body temperatures stored in RAM 203. Second, CPU 201determines the inflection points which are minimums from among theinflection points along the curve. Third, when these inflection pointsare within the deep sleep interval, then CPU 201 specifies a specifictime period centered around the clock time (measured clock time) of theinflection point as the sedate period, and reads out the pulse ratecorresponding to this time as a standard value from RAM 203. In thiscase, it is also acceptable to obtain as the standard value an averagevalue for the pulse rate obtained during the specified sedate period. Inthis way, the pulse rate when the subject is in (or near) his basalmetabolic state is obtained.

CPU 201 corrects the information of the regression formula stored in RAM201 in accordance with a method described above, based on the pulse ratewhich serves as the standard value and on the subject's basal metabolism(see FIG. 10B).

When it is not possible to specify a sufficiently long deep sleepinterval, when the inflection point at which the minimal value wasobtained was not within the deep sleep interval, or when a sedate periodcould not be specified because an inflection point where there was aminimum vale could not be obtained, then it is preferable to provide adesign in which CPU 201 provides notice of that fact on display 205, anddoes not carry out correction of the regression formula information.

2-7-1: Calculation of calorie expenditure

The specific operation for using a calorie expenditure measuring deviceto calculate calorie expenditure will now be explained. This calculationoperation is carried out by executing interrupt processing (1) shown inFIG. 17 at unit time intervals (fixed time intervals of one minute, forexample). Interrupt processing (1) is executed by CPU 201 based on theinterrupt signal from watch circuit 208.

First, at step Sa1, CPU 201 inputs the pulse wave signal from pulse wavedetector 111 via pressure sensor interface 210, and determines the pulserate.

Next, in step Sa2, CPU 201 inputs the body motion signal from bodymotion detector 101 via body motion sensor interface 209, and decideswhether or not the subject is in an active state by determining thepresence or absence of body motion.

If the subject is in a resting state, then in step Sa3, CPU 201determines whether or not the pulse rate obtained above exceeded thethreshold value. If the pulse rate exceeds the threshold value, then, instep Sa4, CPU 201 inputs the body temperature signal from bodytemperature detector 111 via temperature sensor interface 211, anddetermines whether or not the subject's body temperature exceeds thethreshold value.

If the result of the determination in step Sa2 is "YES", then thiscorresponds to case (1) above. If the result of the determination instep Sa4 is "YES", then this corresponds to case (2) above. Accordingly,in step Sa5, CPU 201 selects the "active" regression formula.

On the other hand, if the result of the determination in step Sa3 is"NO", then this corresponds to case (4) noted above. If the result ofthe determination in step Sa4 is "NO", this corresponds to case (3)above. Accordingly, in step Sa6, CPU 201 selects a "resting" regressionformula.

Next, in step Sa7, CPU 201 determines the oxygen intake quantity bysubstituting the pulse rate determined previously into the selectedregression formula, multiplying this by a coefficient, and calculatingthe calorie expenditure per unit time. In step Sa8, CPU 201 providesnotice of the calculated calorie expenditure on display 205 and storesthe data in a time series in RAM 203.

Accordingly, by carrying out this type of interrupt processing (1), thecalorie expenditure per unit time is displayed and updated at unit timeintervals on display 205. At the same time, the value of the calorieexpenditure per unit time interval is sequentially stored in a timeseries in RAM 203.

2-7-2: Change over time in calorie expenditure, comparison with targetvalue

Next, the operation for carrying out processing during the specific timeinterval, for the values of calorie expenditure per unit time which arestored in RAM 203, will be explained. The specific time intervalreferred to here is equivalent to or longer than the interval of timeduring which interrupt processing (1) is carried out, and may be basedon such usual time increment as minutes, hours, days, weeks, months oryears. It is preferable to provide a design which enables selection fromamong these using switches Sw1 or Sw2.

This processing operation is carried out by executing interruptprocessing (2) shown in FIG. 18 at specific time intervals. As in thecase of interrupt processing (1), interrupt processing (2) is carriedout by CPU 201 based on the interrupt signal from time circuit 208.

First, in step Sb1, CPU 201 reads out all the calorie expenditure valuesstored in RAM 203 from the last time interrupt processing (2) wasactivated through the present activation of interrupt processing (2),and adds all these values. In other words, during the specific timeinterval which is the period of interrupt processing (2), all of thecalorie expenditure values which were determined at each unit timeaccording to the execution of interrupt processing (1) described aboveare added, and the calorie expenditure during the specific time intervalis calculated. If "hour" is selected as the specific time interval, thenthe calorie expenditure during one hour is calculated, while if "day" isselected, then the calorie expenditure during one day is calculated.

Next, in step Sb2, CPU 201 provides notice of the summed calorieexpenditure on display 205, and, in step Sb3, stores the summed calorieexpenditure value in a time series in RAM 203. The notification in stepSb2 is, for example, by means of a numerical display of the calorieexpenditure. However, a variety of other arrangements might beconsidered.

In step Sb4, CPU 201 reads out the stored summed values for calorieexpenditure over the past 30 minutes, for example. In step Sb5, CPU 201carries out control so that a 2-dimensional display is realized ondisplay 205 by sequentially plotting the read-out summed values on they-axis and the recorded time interval on the x-axis. An example of thedisplay on display 205 in this case is shown in FIG. 19. As shown inthis figure, it is clear how calorie expenditure transitions during thespecific time interval. Thus, this is beneficial to the subject as anindicator for subsequent exercise. Note that the specific interval oftime in the example in this figure is "day".

Next, in step Sb6, CPU 201 determines whether or not the target valuefor calorie expenditure during the specific period of time has been setin RAM 203. This target value is, for example, set by the subject or athird party such as a physician by means of switch Sw1 or Sw2 or throughcommunication with an external device.

When the results of this determination are "NO", then the followingprocessing is not necessary, and CPU 201 concludes the current interruptprocessing (2).

On the other hand, when the result of this determination is "YES", thenCPU 201 compares the summed value from step Sb1 and the target value,and calculates the achievement rate G with respect to the target valuefrom the following formula.

    Achievement rate G=(summed value/target value)×100

Next, in step Sb8, CPU 201 displays the numerical value of theachievement rate G on display 207. In addition to a simple numericaldisplay, however, a bar graph such as shown in FIG. 20 or a pie chartsuch as shown in FIG. 21 is also possible. Note that in the case of abar graph or pie chart, the target value is indicated by means of themark "∇", so that the relationship between the target and the calorieexpenditure which has been summed at the current point in time may beunderstood at a glance. The specific time interval is "one day" in theexamples shown in FIGS. 20 and 21. In addition, as shown in FIG. 22, aface chart may also be displayed in response to the achievement rate G.

After notification, CPU 201 should carry out the next processing, andend the current interrupt processing (2).

By executing interrupt processing (2), the summed value of calorieexpenditure during the specific time interval is displayed and renewedon display 205 at each specific time interval. In addition, the changeover time in this value is also displayed. If a target value is set,then the subject is notified of the achievement rate G with respect tothe target value, or by a face chart corresponding thereto.

The preceding is the result of combining interrupt processing (1) and(2). However the same effect can be achieved by combining the followinginterrupt processing (3) and (4).

2-7-3: Calculation of calorie expenditure, subtraction from target value

Interrupt processing (3) is executed at each unit time interval, and, inthe same manner an interrupt processing (1), the calorie expenditure iscalculated at this time. However, interrupt processing (3) differs frominterrupt processing (1) in that it does not sequentially store thecalorie expenditure, but subtracts this value from the target value forthe specific time interval. Accordingly, it is possible to calculate theachievement rate G with respect to the target value from the start ofinterrupt processing (3) through the elapse of the specific timeinterval by examining the result of the subtraction operation. Thiscalculation is carried out by executing interrupt processing (4) at thespecific time interval.

An explanation of interrupt processing (3) will now be made withreference to FIG. 23. First, in step Sc1, CPU 201 determines whether ornot a target value for calorie expenditure during a specific time periodhas been set in RAM 203. This target value is, for example, set by thesubject or a third party such as a physician by means of switch Sw1 orSw2 or through communication with an external device.

When the results of this determination are "NO", then the followingprocessing is not necessary, and CPU 201 promptly concludes the currentinterrupt processing (3).

On the other hand, when the result of this determination is "YES", then,in step Sc2, CPU 201 determines whether or not the value of register nis zero. Register n is cleared to zero when interrupt processing (4) iscarried out, and is incremented by "1" each time interrupt processing(3) is executed. Accordingly, when register n is zero, this indicatesthat interrupt processing (3) is being carried out for the first timesince the previous interrupt processing (4) was executed.

If the result of this determination is "YES", then, in step Sc3, CPU 201sets the target value in register TEMP, or skips Sc3 if the result ofthis determination is "NO".

Steps Sc4˜Sc10 are equivalent to steps Sa1˜Sa7 in interrupt processing(1). In other words, CPU 201 selects the regression formula which shouldbe used after taking into consideration the subject's resting/activestate, and psychological state, and calculates the value B for calorieexpenditure per unit time.

When calculating value B, CPU 201 subtracts value B from register TEMPin step Sc11. The result of this subtraction operation is set as the newregister TEMP value. In step Sc12, the subject is notified of the valueof register TEMP which was the result of this subtraction operation viadisplay 205.

Accompanying execution of the current interrupt processing (3), CPU 201increments the value of register n by "1", and concludes processing.

Thus, when interrupt processing (3) is carried out for the first timesince the execution of the previous interrupt processing (4), the targetvalue is set in register TEMP. Subsequently, interrupt processing (1) isrepeatedly carried out at each unit time interval, with the calorieexpenditure subtracted from the register TEMP, and the subject notifiedof the results of this subtraction operation. Accordingly, the calorieexpenditure is subtracted from the target value each time interruptprocessing (1) is carried out.

2-7-4: Comparison with target value

Interrupt processing (4) will now be explained with reference to FIG.24. Interrupt processing (4) is executed at specific time intervals,with its significance being equivalent to as that of interruptprocessing (2).

First, in step Sd1, CPU 201 compares the target value with the value inregister TEMP currently, and calculates achievement rate G with respectto the target value using the following formula.

    Achievement rate G=(target value-TEMP/target value)×100

Next, in step Sd2, CPU 201 displays the numerical value of theachievement rate G on display 207. In this case, a display based onnumerical values such as shown in FIGS. 20 and 21, or a face chart suchas shown in FIG. 22 may also be displayed in response to the achievementrate G.

Accompanying the execution of interrupt processing (4), in step Sd3, CPU201 clears the value in register n to zero, and provides it to interruptprocessing (3) which will be executed immediately thereafter.

As in the case of interrupt processing (1) and (2), by carrying outinterrupt processing (3) and (4) in this way, it is possible to know theachievement rate G of the calories actually used with respect to thetarget value for calorie expenditure during the specific time interval.

2-7-5: Notification of the rate of change

In the above-described interrupt processing (2) and (4), the achievementrate G for the calories actually expended was determined with respect toa target value for calorie expenditure during a specific time interval.Here, for example, when the specific time interval is assumed to becomparatively short, such as 10 minutes, then, provided that the extentof change compared to the value 10 minutes before, i.e., the rate ofchange during the time interval, is known, it is possible to intuitivelyknow the degree of activity which is necessary to reach the goal bysetting the characteristics of the change over time as the desired goal.

This rate of change is calculated by reading out from RAM 203 thecalorie expenditure which was calculated prior to the specific timeinterval, and then dividing the change between this calorie expenditureand the current calculated calorie expenditure by a time periodcorresponding to the specific time interval. It is acceptable to notifythe subject of the calculated rate of change on display 205. In thiscase, the subject or a third party such as a physician sets a targetvalue for the rate of change in RAM 203. On the other hand, whenactually calculating the rate of change, it is acceptable to provide adesign in which notice is provided by calculating the achievement rate Gwith respect to the target value. In addition, the calculated rate ofchange may be stored in RAM 203 in a time series.

2-7-6: Communication function

Next, an explanation will be made of the operation in the case where thecalorie expenditure measuring device according the present embodimentcarries out the sending and receiving of a variety of informationthrough communication with the external device shown in FIG. 9.

When carrying out communication with the external device, the subjectdirects the LED and phototransistor of device main body 300 shown inFIG. 3 toward the communications window 606 of the external device.

The transmission function for sending information to the external deviceand the receiving function for receiving information from the externaldevice will be explained separately.

2-7-6-1: Transmission function

The LED and phototransistor of device main body 300 are exposed and aredirected opposite the communications window 606 of the external device.In this state, the subject operates switch Sw2 and sets the device inthe mode for carrying out the transmission function. Then, CPU 201 inFIG. 2 sends the following information to device main body 600 via I/Ointerface 209 and the optical interface of the external device. In otherwords, CPU 201 sends the calorie expenditure at each unit time intervalstored in a time series in step Sa8 of interrupt processing (1), thesummed value for calorie expenditure during the specific time intervalstored in a time series in step Sb3 of interrupt processing (2), or therate of change in the calorie expenditure which is stored in a timeseries. In this case, it is also acceptable to provide a design in whichthe body motion detected by the body motion detector 101 means, the bodytemperature detected by the body temperature detector 101, and the pulserate calculated by pulse rate calculator 114 are stored in RAM 203 in atime series, with these values being suitably selected and sent to theexternal device. An IrDA (Infrared Data Association) method may be usedas an optical communications protocol in this case.

Transmission is thereby carried out from device main body 300, so thatnot only the subject, but also a third party such as a coach orphysician is able to objectively know how calorie expenditure by thesubject is changing. In addition, storage and analysis of thisinformation is possible as a result.

The information sent by device main body 300 is processed at theexternal device side. As a result, it becomes unnecessary to carry outprocessing for notification of the change in calorie expenditure overtime in step Sb5 or the achievement rate G at the device main body 300side. As a result of this design, the processing load which must becarried out by device main body 300 can be reduced.

2-7-6-2: Receiving function

A target value for calorie expenditure during a specific time intervalis set in the external device as a result of analysis by the subject ora third party such as a physician of the subject's calorie expenditure.It is also acceptable to set a target value for the rate of change incalorie expenditure during the specific time interval.

The LED and phototransistor of device main body 300 are directedopposite the communications window 606 of the external device. In thisstate, the subject operates switch Sw2 and sets the device in the modefor executing the receiving function. Then, the CPU 201 in FIG. 2 sendsa signal indicating a data request to the external device, via I/Ointerface 207 and the optical interface of the external device. Afterreceiving the signal, main body 600 of the external device sendsinformation which will become the set target value, via the opticalinterface of the external device and I/O interface 207.

When the information which will become the target value is received atthe device main body 300 side, then CPU 201 stores the receivedinformation in RAM 203, and sets the information as the target value insteps Sb6, Sc1, etc.

It is also acceptable to set the target value so that it changes overtime. In this case, the target values which correspond to the executiontimes are used for the target values in steps Sb6, Sc1, etc.

By means of the calorie expenditure measuring device according to thepresent embodiment, it is possible to calculate the calorie expenditureper unit time with excellent accuracy, since a suitable regressionformula is selected after taking into consideration each of theresting/active states of the subject, as well as his psychologicalstate. The subject's basal metabolic state is specified, the regressionformula is corrected in response to this, and the monthly or annualchanges in the subject's physiological state are taken intoconsideration. As a result, it is possible to obtain a more accuratedetermination of calorie expenditure. For this reason, the calorieexpenditure measuring device according to the present embodiment isextremely useful in the management of health.

In addition, as a result of the calorie expenditure measuring deviceaccording to the present invention, it is possible to known the calorieexpenditure per unit time, as well as the change in calorie expenditureover time and the success ratio with respect to the target value for aspecific time interval, making the device useful to the subject.

2-8: Deep body temperature and processed result thereof

In addition to being employed in the calculation of calorie expenditure,the body temperature which is sufficiently close to the subject's deepbody temperature that is measured in this embodiment is also extremelysignificant from the perspective of clinical medicine. Further, sincebody temperature is measured using a device which is carried aboutportably by the subject, the present embodiment does not present ahindrance to the subject's daily activities and therefore represents animprovement over the previous art.

An explanation will now be made of the case where the subject or a thirdparty is notified of the obtained deep body temperature and the resultfollowing processing thereof.

In this case, the subject selects the function for measuring bodytemperature by depressing switch Sw2, and indicates the start of bodytemperature measurement by pressing switch Sw1.

Then, first, in the same manner as when calculating the calorieexpenditure, CPU 201 in FIG. 2 recognizes the depression of theaforementioned switch via a switch interface 204. Second, CPU 201sequentially reads out the pulse wave signals from pressure sensorsPs1˜Ps6 via pressure sensor interface 210, and stores these in RAM 203.Third, CPU 201 selects the largest value from among the six measuredpressure values, and specifies the pressure sensor which measured thismaximum pulse pressure. Then, CPU 201 sets the device so thatmeasurements are carried out using the specified pressure sensor and itspaired temperature sensor. Here, it is pressure sensor Ps3 which hasdetected the maximum pulse pressure from among pressure sensors Ps1˜Ps6.When the measured value of the maximum pulse pressure exceeds a specificvalue, then at this time CPU 201 carries out control so thatnotification that a pulse is being detected is provided to display 205.This notification may be carried out by means of a letter display suchas "detecting pulse". Alternatively, a "∘" may be displayed to indicatedetection is being carried out, while an "x" may be displayed toindicate that detection of the pulse is not being performed. As a resultof this notification, it is possible for the subject to know that thebody temperature measurement is being correctly carried out.

Next, CPU 201 carries out settings so that an interrupt is generated atspecific time intervals (every 10 minutes, for example) with respect towatch circuit 208. Thereafter, when the interrupt is generated, CPU 201takes up via temperature sensor interface 211 the measured temperaturevalue at temperature sensor Ts3 which is disposed near pressure sensorPs3, i.e., CPU 201 takes up the digital signal which expresses a bodytemperature which is sufficiently close to deep body temperature. Thecurrent time taken up from watch circuit 208 and the aforementionedmeasured temperature value are then stored as a pair in RAM 203. CPU 201displays the current measured temperature value as the current bodytemperature on display 205.

Subsequently, each time an interrupt is generated by watch circuit 208,CPU 201 repeats the operations to display the measured temperature valueat temperature sensor Ts3 on display 205 and store this measuredtemperature value and the time of measurement together as a pair in RAM203.

When the subject wants to know the change in body temperature over time,he may depress switch Sw2 to select that function. As a result, CPU 201reads out from RAM 203 the measured temperature values and the time ofmeasurement for a specific portion of time from the current time, and,if needed, interpolates between each of the measured points using asuitable interpolation method. The data is then converted to displaydata and sent to display 205. As a result, a graph such as shown in FIG.37 is displayed on display 205. In the figure, time [hours] is plottedalong the horizontal axis, while temperature [° C.] is along thevertical axis.

When it is no longer necessary to measure body temperature, the subjectagain presses switch Sw1, and CPU 201 concludes the processing tomeasure body temperature by releasing the settings in watch circuit 208.

Note that in this design, it is also acceptable to send the measuredtemperature value and the time of measurement which constitute a pairrecorded in RAM 203 to device main body 600 shown in FIG. 9. As aresult, it becomes possible for not only the subject, but also a thirdparty such as a coach or physician to objectively know how the deep bodytemperature of the subject has changed. Further, the storage andanalysis of this information is also possible.

It is also acceptable to provide a design which displays the results ofthe derivative of body temperature with respect to time. If theseresults are displayed, it becomes possible to know the trend, etc. ofthe change in body condition.

In the case of this design, the device is formed so as to carry outmeasurements using a portable device such as a wristwatch, with theposition of the artery automatically detected. As a result, there is noburden on the subject, and the measurement of a body temperature whichis sufficiently close to deep body temperature can be carried outcontinuously. Accordingly, the device is useful in the management ofhealth.

By realizing an accuracy of measurement of, for example, 0.1 [° C.], itis possible to obtain a continuous measurement of body temperature,while the subject himself is able to know the cyclical change in bodytemperature. This is extremely useful when carrying out healthmanagement. Further, the subject is able to know his "quality of life"(QOL) level, and use this as a basis for carrying out appropriatelifestyle activities to improve his QOL.

Although body temperature measured in this way is obtained at thesurface of the subject's body, the temperature is deemed to besufficiently close to the deep body temperature as described above.Since factors such as the temperature of the external environment or theevaporation of sweat from the body surface do not readily have an effecton this measurement, the body temperature obtained in this way may beused as one useful index showing the subject's own state.

2-9: Physiological information for basal metabolic state, and results ofprocessing thereof

Physiological information at the basal metabolic state (or a state closeto it) which is specified in this embodiment should be such standardvalues as the monthly or annual change in the subject's physiology, asdescribed above. Accordingly, as in the case of the deep bodytemperature, this information is useful not only in the calculation ofcalorie expenditure, but is itself extremely significant. For example,if a standard value for physiological information is measured over along period of time such as a month or a year, it is possible to alwaysknow the natural changes in body. Thus, this is useful in a physicalexam or in managing body condition. Moreover, in the case of the deviceof the current embodiment, no hindrance is presented to the subject'sdaily activities.

In addition to the temperature sensor for measuring the subject's bodytemperature, a design is preferable in which a temperature sensor isprovided for measuring the temperature of the external environment(environmental temperature) as an optional structural component of thedevice. The reason for measuring the environmental temperature in thisway is so that the difference between the environmental temperature andthe body temperature can be obtained as a comfort index, as this hassome effect on the subject's psychological and physical state. It isalso acceptable to provide a design which not only provides notificationof the physiological state, but in which a suitable regression formulais selected when calculating calorie expenditure, as was explainedabove.

Notification of the physiological information at the basal metabolicstate and the processed result thereof to the subject or a third partywill now be explained.

First, physiological information in this embodiment includes suchfactors as body temperature, pulse rate and respiration. The method forcalculating body temperature and pulse rate have already been explained,so that the method for calculating the respiration rate from the pulsewave signal from pulse wave detector 111 will be explained here.

In an electrocardiogram, the interval between the R wave of oneheartbeat and the R wave of the next heartbeat is referred to as the RRinterval. FIG. 38 shows heartbeat and the RR interval obtained from thewaveform of this heartbeat in an electrocardiogram. As may be understoodfrom this figure, an analysis of the measured results in anelectrocardiogram reveals that the RR interval varies over time.

On the other hand, variation in blood pressure measured at the peripherysuch as the radius artery or the like, is defined as the variation inblood pressure at each beat from contraction to relaxation of the heart,and corresponds to variation in the RR interval in an electrocardiogram.By carrying out spectral analysis of variations in the blood pressure,it may be understood that the variations are composed of waves having aplurality of frequencies, as shown in FIG. 39A. These may be classifiedinto the following three types of variation components.

1. HF (high frequency) component which is the variation coinciding withrespiration

2. LF (low frequency) component which varies with a periodicity ofaround 10 seconds

3. Trend which varies with a frequency which is lower than themeasurement limits

In order to obtain the respiration rate, CPU 201 first inputs the pulsewaveform from pulse waveform detector 111 over a specific time interval(for example, 30 to 60 sec), and stores these in RAM 203. Second, CPU201 carries out peak detection processing on all the inputted pulsewaveforms, and determines the time interval, i.e., the RR interval,between the peaks of two adjacent pulse waves. Third, each RR intervalobtained is interpolated using an appropriate method (for example, 3rdorder spline interpolation). Fourth, CPU 201 carries out spectralanalysis by performing an FFT (fast Fourier transform) operation on thecurved lined after interpolation. The spectrum obtained as a result isshown in FIG. 39B. CPU 201 determines the maximum values in the spectrumand the frequencies corresponding to these maximum values, sets themaximum value obtained in the high frequency region to the HF component,and obtains the respiration rate from the frequency of the HF component.In the examples shown in FIG. 39A and 39B, the frequency near 0.25 Hz isthe HF component, so that the respiration rate per minute is 0.25×60=15times. Since the RR interval is the period of the pulse beat, CPU 201can obtain the inverse of the RR interval as the pulse rate.

Next, when providing notification of physiological information at thebasal metabolic state, the following modes are envisioned in the presentembodiment. Namely, there is provided a "standard value measuring mode"for measuring and recording each of the standard values of pulse rate,respiration rate, and body temperature, a "standard value display mode"for providing notification of the standard values stored in the standardvalue measuring mode, and a "current value measuring mode" whichmeasures the current pulse rate, respiration rate and body temperature,and notifies the subject of these results.

2-9-1: Operation of standard value measuring mode

In the standard value mode, CPU 201 specifies the deep sleep interval asexplained in section 2-6₋₁ above, determines the pulse rate, bodytemperature, and respiration rate at specific time intervals by means ofthe methods described above, and writes this information into RAM 203 inassociation with the time of input.

Then CPU 201 specifies a sedate period as explained in section 2-6-1above, and determines the standard values for this period, and writesthem into RAM 203 in association with the date and time of input.

Accordingly, when the deep sleep interval and sedate period arespecified, then the standard values for pulse rate, body temperature,and respiration rate, i.e., the physiological information when thesubject is in (or close to) the basal metabolic state, are stored in RAM203.

Note that in this design as well, it is acceptable to transmit thephysiological information, which has been associated with a date andtime of input in RAM 203, to device main body 600 shown in FIG. 9. Inthis way, it is possible for not only the subject, but also a thirdparty such as a physician or coach, to objectively know how each ofthese basic values varies in the subject. Further, storage and analysisof this information is also possible. In the case of the followingdiscussion, the various types of processing will be carried out in adevice main body 300 which has the structure of a wristwatch.

2-9-2: Operation of standard value display mode

In the standard value display mode, notice of information related to thestandard values measured in the standard value measuring mode isdisplayed on display 205 in response to the operational details inputvia switches Sw1 and Sw2.

For example, when a directive is given to display recent standardvalues, then, based on the current date and time of measurement, CPU 201reads out recent standard values, the temperature of the surroundingenvironment at the time of measurement, and the time of the measurement,from RAM 203, and displays these on display 205. An example of thedisplay shown on display 205 in this case is shown in FIG. 40. In theexample shown in this figure, the [45], [15] and [36.3] shown in area205₁ are the standard values for pulse rate, respiration rate, and bodytemperature, respectively, while [22], [12/17], and [4:08] are thetemperature of the surrounding environment at the time of measurement,the date of the measurement, and the time of the measurement,respectively. This enables the subject to know the time of the sedateperiod during the most recent day on which measurements where conducted(the current day, for example), each of the standard values for thepulse rate, respiration rate, and body temperature, and the temperatureof the surrounding environment at the time when each of the standardvalues were measured.

In the case of this display, when the maximum and minimum values whichare associated with the read out standard values are recorded in RAM203, CPU 201 directs a flashing display of the numbers indicating thestandard values (pulse rate, respiration) which are associated with themaximum and minimum values. It is of course acceptable to carry outnotification using a method other than a flashing display. Thus, it ispossible for the subject to know whether or not his physiological statewhile sedate is abnormal, or whether or not the threshold value T whichis employed when specifying a deep sleep interval is suitable.

CPU 201 reads out past standard values from prior to the previous dayand the temperature of the surrounding environment when the measurementswere taken from RAM 203, and displays on display 205 the change overtime through the present day in each of the standard values and thetemperature of the surrounding environment when the measurements weremade. In the example shown in FIG. 40, this change is displayed as adashed line graph in area 205₂. The line graph linking the "∘" symbolsis the standard value for the pulse rate, the line graph linking the "□"symbols is the standard value for respiration, the line graph linkingthe "Δ" is the standard value for body temperature, and the line graphlinking the "x" expresses the change in the temperature of theenvironment when the measurements were made. The time increments notedin the horizontal direction in the figure may be selected in units ofone week, one month, or one year, according to the specific operationscarried out by the subject.

By displaying each of the standard values in the form of a graph in thisway, it becomes possible for the subject to estimate his own biorhythms,and to discover when a deviation from these rhythms has occurred.Further, by studying the biorhythms for the day on which the deviationoccurred, the subject will be able to adjust his biorhythms so that adeviation does not occur.

When a specific operation is generated from switch Sw1 and Sw2, CPU 201converts the standard values measured on the most recent day prior tothe previous day to a graph, and displays the graph in area 205₂ whichis disposed in the same way as the display in area 205₁. In other words,the data from the current day and past data from before the previous dayare displayed in contrast. When a specific operation is carried out inthis state, CPU 201 switches the data displayed in area 205₂ in orderfrom the data of the previous day, the data from the previous week, thedata of the previous month, and the data of the previous year. When datafor the corresponding day is absent, then data from the day (excludingthe current day) which is closest to that day is displayed (in the casewhere there is more than one day which is closest to the day which islacking data, then any of these days may be used). As a result, thesubject is able to correctly know the amount of change in the standardvalues.

2-9-3: Operation of the current value measuring mode

In the current value measuring mode, CPU 201 measures the current pulserate, respiration, body temperature, and the temperature of thesurrounding environment. The results of this measurement are displayedin area 205₁ or 205₂. CPU 201 switches the area in which display isconducted in response to operations by the subject. Here, whendisplaying each of the current standard values in area 205₂, the subjectis able to compare the standard values for the current day, which aredisplayed in area 205₁. Thus, it is possible for the subject to know thedegree of daily change based on his own physiological state.

As explained above, in this embodiment, by notifying the subject ofphysiological information for the basal metabolic state, the subject isable to know the fundamental quantity of his own activity. Moreover,since the device is in the form of a wristwatch, it can of course beworn during the day, but also at night without applying a burden on thesubject. Thus, measurement of the standard values described above iseasily accomplished. Further, since past standard values are recorded inRAM 203, confirmation of these values is always possible.

Since the temperature of the surrounding environment when themeasurements are made is recorded and displayed in association with eachof the standard values, the relationship between these can be understoodby the subject. Once proficient, it is possible for the subject toaccurately know the physiological state when sedate by referring to themeasured values (standard values) for pulse and respiration after takinginto consideration the difference between body temperature and thetemperature of the surrounding environment. Note that it is alsoacceptable that in the standard value measuring mode and the standardvalue display mode, CPU 201 determine the aforementioned difference, anddisplay this difference along with the standard values in the standardvalue display mode, thereby reducing the burden on the subject.

Note that management of body condition may be carried out on a dailybasis by using each of the obtained standard values as standard data forthe amount of activity. For example, as shown in FIG. 42, the heart rate(pulse rate) rises as the environmental temperature increases. There isalmost no difference between individuals with respect to the breadth ofthis increase. Accordingly, if the standard data for the amount ofactivity and the environmental temperature at the time the measurementswere made is obtained, then it is possible to specify the ideal pulserate at an optional environmental temperature. If this ideal pulse rateis then compared with the actual pulse rate, it is possible to determinethe quality of body condition. However, since the standard data for theamount of activity changes with the passage of days, it is possible foran error to be made when determining the quality of the body conditionby assuming this value to be fixed. Thus, if the standard value of thepulse rate (and the environmental temperature when the measurements weremade) obtained in this embodiment is used as standard data for theamount of activity, it is possible to accurately determine the qualityof the body condition by taking into account the change in the data asdays go by.

Similarly, this is also applicable in the case where determining thequality of body condition by monitoring the pulse rate when varying theload on the subject.

3: Example Applications and Modifications of the Present Embodiment

The following example applications and modifications are possible in thecase of the above-described embodiment.

3-1: Example application and modification with respect to structure

The preceding embodiment employed a design where calorie expenditure wascalculated directly from the pulse rate and the presence or absence ofbody motion. However, it is also acceptable to provide a design in whichinformation such as pulse rate and the presence or absence of bodymotion are stored in RAM 203 in a time series, and this information isread out on the following day to calculate the calorie expenditure. Adesign is also possible in which this information is relayed to anexternal device, where the calorie expenditure is then calculated. Inany case, by means of the structure shown in FIG. 1, the calorieexpenditure is calculated by calculating the pulse rate and the presenceor absence of body motion which are read out from RAM.

The preceding embodiment employed two regression formulas, one for whenthe subject is at rest and one for when the subject is active. However,the present invention is not limited thereto. Rather, a design may beprovided in which the characteristics of the curved line shown in FIG.10A are approximated by means of three or more regression formulas, withthe applicable regression formula selected in response to bodytemperature, body motion, and pulse rate. Moreover, the presentinvention is not limited to a linear regression formula. Rather, it isalso acceptable to provide a design in which the curved line isapproximated using an exponential function or an nth order function, ora design in which a plurality of these approaches is employed.

In the preceding embodiment, 6 pairs of temperature and pressure sensorswere employed, with the position at which a maximum pulse pressure couldbe measured selected, and body temperature measured at this site. This,however, is just one example, and it is of course acceptable to increaseor decrease the number of pairs of temperature and pressure sensors. Atone extreme is the device shown in FIG. 25, for example, in which justone pressure sensor and pulse sensor each are employed. As shown in thisfigure, in this design, fastener 302 is attached in a freely slidingmanner to band 301, with pressure sensor Ps and temperature sensor Ts,which comprise one pair, formed in a unitary manner to fastener 302.

As shown in FIG. 26, when using this device, device main body 300 iswrapped around the left arm of the subject. Device main body 300 isfixed in place at a position where the maximum pulse pressure can beobtained by moving fastener 302 in a trial and error manner, so thatpressure sensor Ps and temperature sensor Ts (which cannot be seen inFIG. 26 since they are positioned on the skin surface) which areprovided to fastener 302 are positioned in the vicinity of radial arteryTM.

On the other hand, if the number of sensor pairs is increased, then therange of measurement of pressure is extended and the accuracy of thedisposed sensors can be increased. Thus, it is possible to obtain a moreaccurate measurement of body temperature.

While the pulse waveform can of course be obtained using pressure sensorPs, the use of pressure sensor Ps in the preceding embodiment is reallyfor the purpose of measuring the deep body temperature. In other words,pressure sensor Ps was employed because it is necessary to specify aposition near an artery and measure the temperature at that position.

Accordingly, it is also acceptable to detect the pulse waveform by somemeans other than pressure sensor Ps. For example, a design may beconsidered in which the pulse waveform is detected by means of the pulsewave detector 111 shown in FIG. 27A. In this figure, pulse wave detector111 has a sensor 320 which is formed of a blue LED and a light receivingelement, and is blocked from light by sensor fixing band 321. As shownin FIG. 27B, pulse wave detector 111 is attached between the base andsecond joint of the subject's left index finger. Light is emitted fromthe blue LED. A portion of this light is reflected by the hemoglobin inthe blood and is received at the phototransistor. The output of thisreceived light is supplied to device main body 300 as a pulse wavesignal, via cable 501.

When employing pulse wave detector 111 in this way, a connector 303 isprovided at the 6 o'clock position on device main body 300. A connectorpiece 304 is provided to one end of cable 501 in a freely detachablemanner. In this way, pulse wave detector 111 is not attached whenemploying the device as an ordinary wristwatch.

An InGaN-type (indium-gallium-nitrogen) blue LED is suitably employedfor the blue LED which makes up pulse wave detector 111. The generatedlight spectrum of a blue LED has a peak at 450 nm, for example, with thegenerated light wavelength region being in the range of 350 to 600 nm.In this case, a GaAsP-type (gallium-arsenic-phosphorous) phototransistormay be used for the light receiving element corresponding to an LEDhaving the light emitting characteristics described above. Thewavelength region of the received light of the phototransistor has, forexample, a main sensitive region in the range of 300 to 600 nm, with asensitive region also present below 300 nm. When a blue LED and aphototransistor such as described above are combined, the pulse wave isdetected in the overlapping wavelength region of 300 to 600 nm.

In the case of outside light, it tends to be difficult for light havinga wavelength region of 700 nm or less to pass through the tissues of thefinger. For this reason, even if the portion of the finger not coveredby sensor-fixing band 321 is irradiated with outside light, the lightdoes not reach the phototransistor through the finger tissue. Rather,only light in the wavelength region which does not influence thedetection reaches the phototransistor. On the other hand, light in thelow wavelength region of 300 nm or less is almost entirely absorbed bythe skin surface. Thus, even if the wavelength region of the receivedlight is set to 700 nm or less, the actual wavelength region of thereceived light is 300 to 700 nm.

Accordingly, it is possible to restrain the impact of outside light,without having to significantly cover the finger. Moreover, theabsorption coefficient of blood hemoglobin with respect to light havinga wavelength of 300 to 700 nm is large, and is several to 100-foldgreater than the absorption coefficient with respect to light having awavelength of 880 nm. Accordingly, as in this example, when light in thewavelength region (300 to 700 nm) in which the absorptioncharacteristics are large is employed as the detection light, to matchthe absorption characteristics of hemoglobin, then the detected valuevaries with good sensitivity in response to changes in the blood volume.Accordingly, it is possible to increase the S/N ratio of the pulse wavesignal which is based on the change in blood volume.

Further, it is also acceptable not to provide a body motion detector 101or the like, but rather to obtain the intensity of body motion based onthe pulse waveform detected by pulse wave detector 111. For furtherexplanation, FIG. 41 shows an example of the frequency spectrum of thepulse waveform when the subject swings his arms with a fixed stroke. Inthis figure, S1 is the fundamental wave of body motion (stroke), S2 isthe second higher harmonic wave of body motion, and M1 is thefundamental wave of the movement of blood through the arteries. As isclear from this figure, FFT or other frequency analysis processing iscarried out on the pulse waveform. The frequency component accompanyingbody motion (body motion component) and the frequency componentaccompanying pulse (pulse wave component) are obtained from the resultsof this analysis. Accordingly, for the results of this frequencyanalysis, frequency components excluding the pulse wave components aredefined as the body motion component. By studying the level of the bodymotion component, it is possible to obtain the intensity of body motion.In other words, it is possible to realize a step to determine whether ornot body motion is present without employing a body motion detector 101,or the like. Of course, if the level of the body motion component isdetectable, then it is also possible to use a frequency analysis methodother than FFT.

In addition, the present embodiment measured the pulse rate,respiration, body temperature and temperature of the surroundingenvironment in the deep sleep interval during which the accelerationlevel was below a threshold value T. However, it is also acceptable tomeasure the pulse rate, respiration, body temperature, temperature ofthe surrounding environment, and the acceleration, and then sequentiallydetermine the deep sleep interval and the sedate period after themeasurement interval is finished.

Although the site of measurement in the preceding embodiments was in thevicinity of the radial artery, the present invention is not limitedthereto. Rather, in addition to the area around the carotid artery, anysite is acceptable provided that it is one at which the pulse can bedetected at a position on the skin close to an artery. In addition tosites above the radius and on the neck, other areas may be consideredincluding the hip joint or a site near the arteries of the upper arm, asshown in FIG. 31. More specifically, examples include the temporalartery, internal carotid artery, brachial artery, femoral artery,arteries at the rear of the neck, arteries at the back of the foot, andthe like. Pressure sensor Ps and temperature sensor Ts are attached tothese sites using adhesive tape, or are fixed in place by means of aband or supporter.

3-2: Calculation of pulse rate employing wavelet conversion

The preceding embodiments employed a structure in which the pulse ratewas determined by carrying out FFT conversion of the pulse wave signal.The present invention is not limited thereto, however. For example, itis also possible to use the results of analysis of the pulse wave signalafter carrying out wavelet conversion, i.e., to use the pulse wave dataof each frequency region.

An explanation will now be made of the structure for carrying outwavelet conversion of the pulse wave signal obtained from the pressuresensor and phototransistor, and obtaining the pulse rate from theresults of this analysis. This structure may be realized by substitutingthe FFT processor shown in FIG. 1 with the structure shown in FIG. 28.

In FIG. 28, wavelet converter 700 carries out conventional waveletconversion with respect to the pulse wave signal MH which is output frompulse wave detector 111, and generates pulse wave analysis data MKD.

In general, in time frequency analysis in which the signal issimultaneously analyzed in both the time and frequency domains, thewavelet forms are the unit by which the signal part is extracted.Wavelet transformation shows the size of the each part of the signalextracted as these units. As the base function for defining wavelettransformation, a function ψ(x) which has been localized with respect toboth time and frequency is introduced as the mother wavelet. Here,wavelet transformation employing the mother wavelet ψ(x) of a functionf(x) is defined as follows. ##EQU1##

In equation (1), b is the parameter employed when translating the motherwavelet ψ(x), while a is the parameter used when scaling. Accordingly,wavelet ψ((x-b)/a) in equation (1) is the wavelet obtained whentransitioning mother wavelet ψ(x) by b only, and scaling it by a only.Since the width of the mother wavelet ψ(x) is extended in correspondenceto the scale parameter a, 1/a corresponds to the frequency.

Frequency corrector 800 carries out frequency correction on pulse waveanalysis data MKD. When comparing data from different frequency regions,it is necessary to correct for the effect of the term [1/a^(1/2) ]corresponding to frequency in the preceding equation (1). Frequencycorrector 800 is provided for this purpose. Namely, frequency corrector800 generates corrected pulse wave data MKD' by multiplying wavelet dataWD by a coefficient a^(1/2). As a result, it is possible to carry outcorrection based on each of the corresponding frequencies, so that thepower density per frequency becomes constant.

Next, the detailed structure of wavelet converter 700 will be explained.FIG. 29 is a block diagram of wavelet converter 700.

In this figure, wavelet converter 700 carries out the processing for thecalculation of equation (1) above, and has the following essentialelements. Namely, wavelet converter 700 consists of a base functionrecorder W1 which records the mother wavelet ψ(x); a scale converter W2which converts scale parameter a; buffer memory W3; parallel translatorW4 which carries out translation; and multiplier W5. Please note thatvarious types of wavelets may be suitably employed for mother waveletψ(x) which is stored in base function recorder W1, including Gaborwavelet, Mexican hat wavelet, Harr wavelet, Meyer wavelet, Shannonwavelet and the like.

When a mother wavelet ψ(x) is read out from base function recorder W1,conversion of scale parameter a is carried out by scale converter W2.Scale parameter a corresponds to period, thus, the bigger a is, the morethe mother wavelet extends above the time axis. In this case, thequantity of data for mother wavelet ψ(x) recorded in base functionrecorder W1 is fixed, so that when a gets larger, the amount of data perunit time decreases. Scale converter W2 carries out interpolation tocorrect this, and generates a function ψ(x/a) by performing weeding outprocessing when a gets smaller. This data is stored once in buffermemory W3.

Next, parallel translator W4 reads out function ψ(x/a) from buffermemory W3 at a timing in response to translation parameter b, carryingout the parallel transition of function ψ(x/a), to generate a functionψ(x-b/a).

Next, multiplier W5 multiplies variable 1/a^(1/2), function ψ(x-b/a) andthe pulse wave signal obtained following A/D conversion, to generatepulse wave analysis data MKD. In this example, the pulse wave signalundergoes wavelet conversion. In this example, the pulse wave analysisdata MDK is segregated into the frequency regions 0 Hz˜0.5 Hz, 0.5Hz˜1.0 Hz, 1.0 Hz˜1.5 Hz, 1.5 Hz˜2.0 Hz, 2.0 Hz˜2.5 Hz, 2.5 Hz˜3.0 Hz,3.0 Hz˜3.5 Hz, and 3.5 Hz˜4.0 Hz, and output.

Correction of this pulse wave analysis data MKD is carried out byfrequency corrector 800, and supplied to pulse rate calculator 114 shownin FIG. 1 as corrected pulse wave data MKD'.

The processing cycle is carried out at an interval which is sufficientlyhigher, 8-fold for example, than the pulse rate which is typicallyassumed. In this case, the corrected pulse wave data MKD' which isgenerated at each heart beat becomes data M11˜M88, shown in FIG. 30B.

Next, an explanation will be made of the case where pulse ratecalculator 114 determines the pulse rate from corrected pulse wave dataMKD'. When examining the pulse components of a typical pulse waveform, asharp rise may be noted in each beat. For this reason, data indicatingthe high frequency components in this rising portion become large.Accordingly, first, pulse rate calculator 114 specifies the changingportion of the high frequency component, third, determines the intervalof this portion, i.e., the interval of the beat, and third, calculatesthe inverse of this interval as the pulse rate.

For example, if corrected pulse wave data MKD' is a value such as shownin FIG. 30C, then the value of data M18 corresponding to this risingportion becomes larger than the values of the other data, such as [10].The pulse interval is judged to be from the time until the next suchvalue is detected, with the pulse rate then determined by taking theinverse of the pulse interval.

3-3: Other examples of the embodiments

The preceding embodiments employed a wristwatch structure for thecalorie expenditure measuring device, however, the present invention isnot limited thereto. A number of examples for the arrangement of thecalorie expenditure measuring device according to the present inventionwill now be explained.

3-3-1: Necklace model

The calorie expenditure measuring device according to the presentinvention may be rendered in the form of a necklace such as shown inFIG. 32.

In this figure, pressure sensor Ps and temperature sensor Ts areprovided to the end of a cable 31, and are attached to the area of thecarotid artery by means of an adhesive tape 39, such as shown in FIG.33. In FIG. 32, essential components of the device may be incorporatedinto a case 32 which is in the form of a broach which is hollow inside.The above-described display 205, switch Sw1 and switch Sw2 are providedto the front surface of this broach. One end of cable 31 is embedded inchain 33, with pressure sensor Ps and temperature sensor Ts electricallyconnected to pressure sensor interface 210 and temperature sensorinterface 211 which are housed in case 32.

3-3-2: Eyeglasses

The calorie expenditure measuring device according to the presentinvention may also be incorporated into a pair of eyeglasses such asshown in FIG. 34.

As shown in the figures, the main body of the device in this embodimentis separated into a case 41a and a case 41b, which are attached to thestems 42 of the eyeglasses, respectively, and are connected electricallyvia a lead wire embedded in stems 42. A liquid crystal panel 44 isattached over the entire surface of the lens 43 side of case 41a. Amirror 45 is fixed to the edge of this lateral surface at a specificangle. A drive circuit for liquid crystal panel 44 which includes alight source (not shown) and a circuit for forming the display data areincorporated in case 41a. These form display 205 shown in FIGS. 2 or 3.The light emitted from this light source passes via liquid crystal panel44, and is reflected at mirror 45 to incident on lens 43 of theeyeglasses. The principle elements of the device are incorporated incase 41b, with switches Sw1 and Sw2 described above attached to theupper surface thereof. On the other hand, pressure sensor Ps andtemperature sensor Ts are electrically connected to pressure sensorinterface 210 and temperature sensor interface 211 which are housed incase 41b, via cable 31. Pressure sensor Ps and temperature sensor Ts areattached to the carotid artery in the same manner as in the case of thenecklace. The lead wires which connect case 41a and case 41b may bedesigned so as to extend along stems 42. In this example, the devicemain body was divided into case 41a and case 41b, however, it is alsoacceptable to employ a case formed in a unitary manner. Mirror 45 may bemoveable so that the user can adjust the angle between the liquidcrystal panel 44 and mirror 45.

3-3-3: Card model

As another example of an embodiment of the present invention, thecalorie expenditure measuring device may be rendered in the form of acard such as shown in FIG. 35. The device in this form is stored in theleft breast pocket of the subject's shirt, for example. Pressure sensorPs and temperature sensor Ts are electrically connected to pressuresensor interface 210 and temperature sensor interface 211 which arestored in a case, via cable 31. As in the case of the necklace, they areattached to the area of the carotid artery of the test subject.

3-3-4: Pedometer

As another embodiment of the present invention, the calorie expendituremeasuring device may be incorporated into the pedometer shown in FIG.36A, for example. The main body of this pedometer device is attached tothe subject's waist belt 51 as shown in FIG. 36B. Pressure sensor Ps andtemperature sensor Ts are electrically connected to pressure sensorinterface 210 and temperature sensor interface 211 housed in a case, viacable 31. They are fixed in place to the area of the femoral artery atthe subject's hip joint by means of adhesive tape, and are protected bysupporter 52. In this case, it is preferable to sew cable 31 into theclothing, so that it does not present a hindrance to the subject's dailyactivities.

3-4: Arrangements for display and notification

The preceding embodiments employed a design in which the calculatedresults were all displayed on display 205; however, the presentinvention is not limited thereto. Namely, a variety of arrangements arepossible for notification, which do not rely on the sense of sight. Inthis sense, notification in the present invention means a method whichrelies on any one of the five senses. For example, a design may beprovided which relies on the sense of sound in which the subject isnotified of the calculated calorie expenditure, achievement rate G, orrate of change by means of a synthesized voice. Similarly, a design isalso possible which relies on the tactile sense by employing vibrationin the notification.

We claim:
 1. A body temperature measuring device, comprising:pulse wavedetecting means for detecting over a specific area the pulse pressurearound the site where the subject's pulse is present; temperaturedetecting means for detecting temperature which is provided near thepulse wave detecting means; and body temperature specifying means forspecifying as the body temperature the temperature detected at the siteat which the largest pulse pressure from among the pulse pressuresdetected in the specific area was detected.
 2. A body temperaturemeasuring device according to claim 1, further comprising a plurality ofpairs of pulse wave detecting means and temperature detectingmeans,wherein the body temperature specifying means specifies as thebody temperature the temperature detected by the temperature detectingmeans corresponding to the pulse wave detecting means which detected thelargest pulse pressure as the body temperature.
 3. A body temperaturemeasuring device according to claim 2, wherein the plurality of pairs ofpulse wave detecting means and temperature detecting means are disposedin rows at roughly a right angle with respect to the direction ofelongation of the arterial vessels at which the detection of pulsepressure is carried out.
 4. A body temperature measuring deviceaccording to claim 1 or claim 2, further comprising storing means forstoring at fixed intervals of time the body temperature specified by thebody temperature specifying means.
 5. A body temperature measuringdevice according to claim 4, further comprising notifying means fornotifying the subject of the change in body temperature over time, basedon the body temperatures stored in the fifth storing means.
 6. A bodytemperature measuring device according to claim 4, further comprisingtransmission means for transmitting the body temperature stored in thestoring means to an external device.
 7. A body temperature measuringdevice according to claim 1 or claim 2, further comprising:pulsediscriminating means which determines whether or not the pulse wavedetecting means is detecting the pulse pressure; and notifying meanswhich notifies the subject of the result of the determination by thepulse discriminating means.
 8. A body temperature measuring deviceaccording to claim 1 or claim 2, further comprising a body motiondetecting means for detecting the subject's body motion,wherein the bodytemperature specifying means specifies the body temperature when adetermination is made that the body motion is within specified limitsbased on the detected results of the body motion detecting means.
 9. Abody temperature measuring device according to claim 1, furthercomprising:basal metabolic state specifying means for specifying thesubject's basal metabolic state from the body temperature specified bythe body temperature specifying means; physiological informationmeasuring means for measuring the subject's physiological information;physiological information specifying means for specifying thephysiological information measured by the physiological informationmeasuring means as the physiological information of the subject's basalmetabolic state, in the case where the basal metabolic state was beenspecified by the basal metabolic state specifying means.
 10. A bodytemperature measuring device according to claim 9, wherein the basalmetabolic state specifying means specifies the minimum in the subject'sbody temperature as the basal metabolic state.
 11. A body temperaturemeasuring device according to claim 9, further comprising body motiondetecting means for detecting the subject's body motion,wherein thebasal metabolic state specifying means specifies the subject's basalmetabolic state when body motion is with specific limits based on theresults of detection by the body motion detecting means.
 12. A bodytemperature measuring device according to claim 9, further comprisingtime keeping means for measuring the current time,wherein the basalmetabolic state specifying means specifies the basal metabolic state inthe case where the current time kept by the time keeping means isdetermined to be within a preset time period.
 13. A body temperaturemeasuring device according to claim 9, further comprising:body motiondetecting means for detecting the subject's body motion; and timekeeping means for measuring the current time; wherein the basalmetabolic state specifying means specifies the basal metabolic state inthe case where body motion is determined to be within specific limitsbased on the results of detection by the body motion detecting means,and the current time kept by the time keeping means is determined to bewithin a preset time period.
 14. A body temperature measuring deviceaccording to claim 9, further comprising:environmental temperaturedetecting means for detecting the temperature of the environment aroundthe subject; and correcting means for correcting the physiologicalinformation measured by the physiological information measuring meansbased on the environmental temperature detected by the environmentaltemperature detecting means.
 15. A body temperature measuring deviceaccording to claim 9 or claim 14, further comprising storing means forstoring physiological information specified by the physiologicalinformation specifying means.
 16. A body temperature measuring deviceaccording to claim 15, further comprising notifying means for notifyingthe subject of a change in the physiological information based on thestored results of the storing means.
 17. A body temperature measuringdevice according to claim 16, wherein the notifying means carries outnotification in response to the deviation between the physiologicalinformation measured by the physiological information measuring meansand the physiological information stored in the sixth storing means. 18.A body temperature measuring device according to claim 15, furthercomprising transmitting means for transmitting the physiologicalinformation stored in the storing means to an external device.
 19. Abody temperature measuring device, comprising:a plurality of pulse wavedetectors each detecting at a respective site a corresponding pulsepressure of a subject; a plurality of temperature detectors eachdetecting a temperature of the respective site corresponding to one ofthe plurality of the pulse wave detectors; and a body temperaturedetector selector to select a detected temperature detected by one ofthe plurality of temperature detectors corresponding to the respectivesite having the largest pulse pressure.
 20. A body temperature measuringdevice according to claim 19, wherein the plurality of pulse detectorsare arranged in a first row and the plurality of temperature detectorsare arranged in a second row.
 21. A body temperature measuring deviceaccording to claim 20, wherein the first and second rows are disposed inrows at roughly a right angle with respect to the direction ofelongation of the arterial vessels at which the detection of pulsepressure is carried out.
 22. A body temperature measuring deviceaccording to claim 19 or claim 20, further comprising a first memory tostore at fixed intervals of time the detected temperature selected bythe body temperature selector.
 23. A body temperature measuring deviceaccording to claim 22, further comprising a notifier to notify thesubject of a change in body temperature over time, based on the bodytemperatures stored in the first memory.
 24. A body temperaturemeasuring device according to claim 22, further comprising a transmitterto transmit the body temperature stored in the first memory to anexternal device.
 25. A body temperature measuring device according toclaim 19 or claim 20, further comprising:a pulse discriminator whichdetermines whether or not the plurality of pulse wave detectors aredetecting the pulse pressure; and a notifier to notify the subject ofthe result of the determination by the pulse discriminator.
 26. A bodytemperature measuring device according to claim 19 or claim 20, furthercomprising a body motion detector to detect the subject's bodymotion,wherein the body temperature selector selects the bodytemperature when a determination is made that the body motion is withinspecified limits based on the detected results of the body motiondetector.
 27. A body temperature measuring device according to claim 19,further comprising:a basal metabolic state specifier to specify thesubject's basal metabolic state from the body temperature specified bythe body temperature selector; a physiological information measurer tomeasure the subject's physiological information; a physiologicalinformation specifier to specify the physiological information measuredby the physiological information measurer as the physiologicalinformation of the subject's basal metabolic state, in the case wherethe basal metabolic state was been specified by the basal metabolicstate specifier.
 28. A body temperature measuring device according toclaim 27, wherein the basal metabolic state specifier specifies theminimum in the subject's body temperature as the basal metabolic state.29. A body temperature measuring device according to claim 27, furthercomprising a body motion detector to detect the subject's bodymotion,wherein the basal metabolic state specifier specifies thesubject's basal metabolic state when body motion is with specific limitsbased on the results of detection by the body motion detector.
 30. Abody temperature measuring device according to claim 27, furthercomprising a timer to measure the current time,wherein the basalmetabolic state specifier specifies the basal metabolic state in thecase where the current time kept by the timer is determined to be withina preset time period.
 31. A body temperature measuring device accordingto claim 27, further comprising:a body motion detector to detect thesubject's body motion; and a timer to measure the current time; whereinthe basal metabolic state specifier specifies the basal metabolic statein the case where body motion is determined to be within specific limitsbased on the results of detection by the body motion detector, and thecurrent time kept by the timer is determined to be within a preset timeperiod.
 32. A body temperature measuring device according to claim 27,further comprising:an environmental temperature detector to detect thetemperature of the environment around the subject; and a corrector tocorrect the physiological information measured by the physiologicalinformation measurer based on the environmental temperature detected bythe environmental temperature detector.
 33. A body temperature measuringdevice according to claim 27 or claim 32, further comprising a memory tostore physiological information specified by the physiologicalinformation specifier.
 34. A body temperature measuring device accordingto claim 33, further comprising a notifier to notify the subject of achange in the physiological information based on the stored results ofthe memory.
 35. A body temperature measuring device according to claim34, wherein the notifier carries out notification in response to thedeviation between the physiological information measured by thephysiological information measurer and the physiological informationstored in the memory.
 36. A body temperature measuring device accordingto claim 33, comprising a transmitter to transmit the physiologicalinformation stored in the memory to an external device.